2 Sexual Selection vs. Natural Selection in Corolla Dimorphisms

Joseph N. Abraham*

University of Louisiana (joe@cajunfun.com)

Some plants have separate sexes, and in some of those plants, the male flowers are larger than female flowers. For several years, we have looked at those differences and assumed that these are explained by what Darwin called Sexual Selection: males compete with each other for the right to mate with females. A larger male flower, it is supposed, will attract more pollinators, which in turn, would mean that the male's pollen is carried to female flowers more often. The problem is, we have other concepts under Optimality Theory, that say animals should only search for food in ways that give them the most calories. So it is not at all clear why an insect would prefer a larger male flower, unless it also includes more food. Either way, the flower size is not the issue; the calories are. A 19th Century contemporary of Darwin's suggested that the larger male flower attracts pollinators, not more often, but first. That is, pollinators visit male flowers before they visit females, so that they are carrying pollen, and thereby efficiently fertilizing the females. My research shows that this latter explanation can be seen in pollinator behavior, but the earlier explanation of male competition is not seen. (Sexual Selection, Sunday 4:30 PM - 4:45 PM, NMM2)

3 Female Mosquitofish (Gambusia holbrooki) prefer larger males

Cindy N. Achat* & Stephen A. Taylor Armstrong

Atlantic State University (psychedatuf@hotmail.com)

There is considerable variance in body size of sexually mature male mosquitofish. We investigated female mosquitofish preferences for larger males versus smaller males, as well as how being deprived of male contact would influence female preferences. Females did show a significant preference for larger males, but male deprivation had no effect on preferences. (Regular Poster Session, Tuesday evening, Gym)

4 Breeding and parental care in songbirds: An evolutionarily stable set analysis

Joel J. Adamson*

University of Colorado (adamsonj@ucsub.colorado.edu)

Male Lark Sparrows Chondestes grammacus, like most songbirds are monogamous and provide care for their young. A two-stage game models the behavior of a male and a female in a breeding situation. In the first stage, males can either mate with one female at a time or breed with multiple females at once. All males provide resources that can be used by one female or shared by multiple females. Females will either condition their output of eggs on the male’s strategy or they will produce the same amount of eggs no matter what the male does. A parental game where male or female can either care or desert follows the mating stage. A set of strategies of female output based on male behavior, males mating with one female at a time, and two-parent care is evolutionarily stable, meaning that no strategy out of those to choose from produces more young. Therefore, in a situation where resources are uniformly distributed, males provide benefits to females and females condition their output on male behavior, we should observe monogamous pairing and biparental care. (Mate Choice 3, Monday 2:45 PM - 3:00 PM, NMM1)

5 The evolution of sex-biased dispersal: inbreeding avoidance and competition

Susan C. Alberts* & Rebecca J. Lewis

Duke University (alberts@duke.edu)

It has long been known that among birds, females tend to leave their home area and move to new territories to breed, while among mammals, it is males that tend to move. Many hypotheses have been proposed to explain both the sex bias in dispersal (the fact that one sex disperses and the other doesn't), and the direction of the bias (the fact that the dispersers are males in some species, females in others). It is widely recognized that the tendency for animals to avoid inbreeding (avoid mating with close relatives) may play a role in dispersal patterns, but inbreeding avoidance alone only predicts that one sex should disperse wile the other remains at home; it does not predict whether the dispersing sex should be males or females. Other factors that might be important are competition for mates and competition for resources, both of which vary between birds and mammals. We present a model that seeks to explain diverse dispersal patterns in one general framework that incorporates the ideas of inbreeding avoidance, competition for mates and resources, and any potential risks associated with dispersal. (Dispersal Symposium, Sunday 2:45 PM - 3:00 PM, Sale)

6 Are biased offspring sex ratios in nests of secondary female House Wrens adaptive? A test of the Trivers-Willard assumptions

Dan Albrecht* & L. Scott Johnson

Sacred Heart University & Towson University (albrechd@sacredheart.edu)

In a Wyoming population of House Wrens, secondary females receive no male parental assistance in rearing their young and produce female-biased offspring sex ratios as predicted by the Trivers-Willard hypothesis. The Trivers-Willard explanation assumes that variation in quality of parental care provided to nestlings has effects that last into their adulthood, and that parents can benefit by producing female offspring more oftne when conditions are poor and males more often when conditions are good. However, before this hypothesis can be supported, it assumptions must be evaluated. I evaluated the appropriateness of this assumption for this study population using a long-term data set to compare the relationship between rearing condition, survival, recruitment, and adult breeding success for individuals fledged from biparental (high quality) care nests and for individuals fledged from uniparental (low quality) care nests. Young from uniparental care nests fledge in poorer condition and have lower rates of survival and recruitment than young from biparental care nests. Overall, it appears that low quality parental care has lasting effects on the young. Adult females may respond to this by skewing their offspring sex ratios when they breed as secondary females. (Regular Poster Session, Tuesday evening, Gym)

10 Natal dispersal and the territory establishment in resident song sparrows

Peter Arcese* & Lukas F. Keller

University of British Columbia & Princeton University (arcese@interchange.ubc.ca)

Young birds must often gain access to exclusive territories in order to breed successfully, and many studies have identified success in territory establishment as a key factor affecting fitness in territorial animals. Nevertheless, little is known about the behavioral mechanisms involved in territory acquisition or its relation to variation in the movement patterns of young birds in the period after they become independent from parental care. The work described in this paper comes from 25 years of detailed work in a small population of song sparrows that resides year-round on a small island in British Columbia, where all birds are color-banded as nestlings and followed thereafter to their death or dispersal from the island. Our work reveals that young sparrows are exceptionally competitive for space and vary widely in their movement tactics. The most successful birds were those that were hatched early each season and that spent their time in small home ranges that encompassed territories defended by 3-6 adults. These birds were socially dominant in local hierarchies of juveniles, and they acquired first, in most cases, the territories of adults that died during the non-breeding period. (Dispersal Symposium, Sunday 11:15 AM - 11:30 AM, Sale)

13 Time and Energy Allocation in Breeding Male Ground Squirrels.

Gwendolyn C. Bachman*

University of Nebraska (gbachman@unlserve.unl.edu)

The mating success of polygynously breeding males may be enhanced by maximizing the allocation of time and energy to activities which promote mate acquisition. Foraging is not likely to directly promote mating success yet it may be necessary to ‘fuel’ breeding efforts. The potential trade-off between foraging and mate acquisition is amplified in ground squirrel species which breed shortly after emerging from hibernation. Time budgets and body composition were examined in two squirrel species: Spermophilus tridecemlineatus (St) and Spermophilus beldingi (Sb). In each, a subset of males received daily food supplements. Relative to a pre-breeding period, foraging decreased in breeding St males but increased in Sb males; both increased searching and running during breeding. In both species, supplemented males foraged less than controls. During the pre-breeding period, St and supplemented Sb males gained more fat-free mass (FFM) than fat though both lost fat during breeding. Sb males also gained FFM during breeding. Foraging during breeding contributed more to fueling energy expenditures in St than in Sb. Habitat differences may affect the importance of foraging during breeding in these species. (Regular Poster Session, Tuesday evening, Gym)

14 Do most colorful birds sing most complex songs? Species divergence in sexually selected traits in finches

Alexander Badyaev*, Geoffrey E. Hill & Byron V. Weckworth

University of Montana, Auburn University (abadyaev@selway.umt.edu)

Elaborate plumage of male birds, and their complex songs are some of the best known examples of sexual traits in animals. In many species, plumage brightness and song complexity play important roles in male-male competition and in female choice. Long ago it was proposed that, animals will generally emphasize the trait that is most conspicuous or that best signals condition and reduce Display of other traits. While this idea has been widely proposed, it is virtually untested. Here we examined the relationships between song complexity and plumage elaboration in cardueline finches, which are highly variable in plumage Display and song complexity but share a similar mating system. We found that song complexity was negatively related to elaboration of carotenoid-based coloration but unrelated to expression of melanin-based coloration. Carotenoid pigmentation, like song complexity, has been shown to be a condition-dependent signal used in mate choice. Melanin pigmentation, on the other hand, is generally not dependent on individual condition. These observations supports the idea that animal species trade-off expression of condition dependent traits, perhaps in response to changes in the costs or the information content of the Display traits. Overall, however, in finches, males of most colorful species sing most simple songs. (Evolution of Signals, Tuesday 10:45 AM - 11:00 AM, NMM1)

16 Rearing influences sexual behavior in captive juvenile chimpanzees

Kate Baker*, Mollie Bloomsmith & Stephen K. Ross

Emory University, Zoo Atlanta, Lincoln Park Zoo, & Yerkes Regional Primate Research Center (kateb@rmy.emory.edu)

A chimpanzee's behavior can be seriously affected by whether it was raised by its mother or by humans. Some infants must be raised in a nursery because their mothers are not able to care for them, so we need to have a good understanding of how different rearing settings affect behavioral development. We used 500 hours of behavioral data collected on 29 male and female juvenile chimpanzees (aged 4 to 6) to assess the influence of rearing on sexual behavior. Mother-reared juveniles showed higher levels of sexual behavior than nursery-reared subjects. All study subjects, however, were observed to copulate, an improvement over the outcome of older nursery-rearing practices. Sexual behavior did not differ between juveniles reared with their mothers for two years and those mother-reared for longer periods. No differences were detected between peer-housed juveniles and those housed in mixed-age groups. Ten female subjects later became pregnant; four of the five pregnancies by nursery-reared subjects ended in spontaneous abortion, while only one of five pregnancies by mother-reared females failed to result in a live birth. This information will enhance our ability to maintain the captive chimpanzee population and to house them in optimal social settings. (Parental Care 2, Sunday 3:15 PM - 3:30 PM, NMM1)

17 Does demography provide evidence for a cost of dispersal?

Mitchell B. Baker*

University of Massachusetts - Amherst (mbbaker@ent.umass.edu)

Dispersal is important because it links populations, allowing genes or diseases to spread, and because it allows re-colonization of areas where populations have gone extinct. How far animals are willing to travel depends among other things on how dangerous movement is. Costs of dispersal are hard to measure, however, because animals can move so far that they can't be observed, and so death and dispersal become indistinguishable. In many species, one sex disperses farther than the other before settling to breed, and I predicted that in those species, the sex that travels farther will be less common in the adult population. I surveyed studies of dispersal in birds and mammals where the two sexes disperse different distances to see if changes in sex ratio support the hypothesis that longer distance dispersal is more risky. I found that sex ratio does tend to shift in the direction predicted if travel is risky, and also that dispersal may be more costly in bird species that have evolved co-operative breeding (where helpers other than the direct parents aid in child-rearing). This possibility is interesting because costs of dispersal have been suggested as one factor leading to the evolution of cooperative breeding. (Dispersal, Sunday 5:00 PM - 5:15 PM, Sale)

19 Female mate-choice in relation to structural plumage coloration in blue grosbeaks

Barbara Ballentine* & Geoffrey E. Hill

Auburn University (ballebe@mail.auburn.edu)

Blue grosbeaks (Guiraca cerulea) are socially monogamous, sexually dichromatic songbirds. Males are almost entirely blue, while females are brown. Previous studies showed that plumage blueness is related to nutritional condition during molt and that bluer males hold larger territories with more food resources. Here we tested the hypothesis that females use male plumage blueness as a criterion in choosing mates. In a mate choice arena, we presented females with a choice between males whose feathers were either artificially brightened with blue marker or artificially dulled with black marker. Treatment of males resulted in changes in color intensity while the wavelength of the color reflected remained unchanged. Thus, we increased the intensity of blue treated males and decreased the intensity of black treated males. During mate-choice trials, females showed consistent preferences for particular males but choice was random with respect to treatment. We found no evidence that blue coloration functions in mate choice in blue grosbeaks. However, previous studies suggest that color in male blue grosbeaks is correlated with male quality. Thus, it seems likely that blue coloration in blue grosbeaks functions in male-male interactions. (Mate Choice 2, Sunday 2:00 PM - 2:15 PM, NMM2)

21 Sexual selection and ornamentation in female birds

Sara Beall*, Jodie Jawor & Randall Breitwisch

University of Dayton (beallsam@hotmail.com)

Ornamentation in female birds has traditionally been viewed as the result of genetic correlation between the sexes and strong sexual selection acting on ornamentation in males. The alternative hypothesis of sexual selection acting directly on females has only recently become the focus of study, and there is evidence supporting the sexual selection hypothesis for, at least, some species (reviewed in Amundsen. 2000. TREE 15:149). In this review, we extend the discussion of the sexual selection hypothesis to ask (1) if either male mate choice or female intrasexual competition is more likely to favor female ornamentation in birds, (2) if particular aspects of female individual quality are more likely than others to favor ornamentation as a predictor of quality, and (3) if greater vulnerability of nesting females to predation can account for less conspicuous ornaments in female versus male birds. (Regular Poster Session, Tuesday evening, Gym)

22 Chemosensory detection of skin lipids from snake predators in the Desert Iguana (Dipsosaurus dorsalis)

Matthew T. Bealor* & C. O'Neil Krekorian

University of Tennessee, Knoxville & San Diego State University (mbealor@utk.edu)

Several species of lizards respond to chemicals from sympatric lizard-eating snakes. These substances elicit antipredator behavior indicating they have important ecological functions. However, the source of chemicals utilized by lizards in detecting potential snake predators has yet to be examined. We tested the ability of adult desert iguanas, Dipsosaurus dorsalis, to detect and identify a potential snake predator by exposing them to lipid extracted from shed snakeskin. Lipid was extracted from cast skins of a known lizard-eating snake, the California kingsnake Lampropeltis getula california, using chloroform/methanol. Test subjects were presented with skin lipid as well as clean, pungent, and chloroform controls on cotton-tipped applicators, in a randomized order. Desert iguanas directed significantly more tongue flicks toward applicators bearing snake lipid than to any of the controls. In addition, overall tongue extrusion frequency increased in response to lipid during the 5-minute trials. Desert iguanas clearly detected the presence of the lipid extract, but a lack of associated changes in posture and movement patterns indicates they failed to associate lipid with a potential threat. (Predator Prey, Monday 1:45 PM - 2:00 PM, NMM2)

24 Lowering pitch during aggressive vocal interactions: Bluffing with an unbluffable signal?

Mark A. Bee*, Stephen A. Perrill, & Patrick C. Owen

University of Missouri, Butler University, & University of Connecticut (mabf79@mizzou.edu)

During aggressive interactions over access to territories, resources, or mates, animals often assess their opponent’s size and fighting ability using information conveyed in communication signals. The pitch of acoustic communication signals is widely regarded as an "unbluffable" signal of size due to size-related physical constraints of sound production. In frogs, the pitch of acoustic signals is negatively correlated with body size, which in turn is positively related to fighting ability. During aggressive territorial interactions, however, male green frogs (Rana clamitans) lower pitch of their acoustic signals, suggesting that males may attempt to bluff their size and fighting ability by producing calls with lower pitch. In a field playback experiment, we tested several hypotheses about the function of pitch alteration in green frogs. Small males decreased pitch more often and by a larger magnitude when faced with a simulated large opponent, but large males did not discriminate between simulated opponents of different sizes. We suggest the possibility that pitch alteration is a form of context-dependent bluffing in which small males produce dishonest signals of size during agonistic interactions they are unlikely to win. (Behavioral Context, Monday 11:45 AM - 12:00 PM, NMM2)

25 Sex differences in mate size preference in the convict cichlid, Cichlasoma nigrofasciatum

Simon Beeching*, Amanda B. Hopp & Ginger L. Ruffner

Slippery Rock University & NIH-NIDDK (simon.beeching@rockmail.sru.edu)

Does size matter? At least in cichlid fishes, we think it should. Both males and females can increase their reproductive success by choosing larger mates. We tested these predictions in the laboratory, and found that males indeed prefer larger mates. However, females did not! These results are surprising, since larger males make for better defenders in the competition for nesting sites. So what do females prefer? It may be that females prefer males who are compatible with their own size and reproductive state, not simply large. It appears that males and females are using different strategies in the evolutionarily significant process of mate choice. (Recognition & Mate Choice, Tuesday 3:15 PM - 3:30 PM, NMM1)

27 The role of male-female conflict in the maintenance of hybridization by the ground crickets Allonemobius fasciatus and A. socius

James H. Benedix, Jr.*

DePauw University (jbenedix@depauw.edu)

The ground crickets Allonemobius fasciatus and A. socius form a zone of overlap and hybridization in which there is selection against the hybrids. However, there is little or no reproductive character displacement in male calling songs or female song preferences. Mating trials were performed in two different years with two different feeding regimes to determine if there was any isolation during the post-advertisement portion of the mating process. In no-choice mating trials, there was only one indication of conspecific mating preferences (food-restricted A. socius), and in group mating trials there was no evidence of preferences. Observations of the conflict between males and females regarding the fate of the spermatophore (i.e. whether it is consumed by the male or the female), suggest that females may benefit by mating multiply, including matings with heterospecific males. Males are hesitant to release their spermatophores after copulation, therefore females may need to mate many times to gather appreciable energy. Because the cost of mating mistakes is reduced by conspecific sperm precedence, there may be a net benefit to mating indiscriminately. Thus the continued low level of hybridization may be maintained by the indirect effects of male-femaleconflict. (Recognition & Mate Choice, Tuesday 3:00 PM - 3:15 PM, NMM1)

29 Can alarm calls be directed to predators?

Carl T. Bergstrom* & Michael Lachmann

Emory University & Santa Fe Institute (dirk@santafe.edu)

When threatened with predation, animals from a wide range of species produce alarm calls; these calls are typical thought to be warnings intended for other individuals of the same species. However, several authors have offered an alternative interpretation: some alarm calls may intended for the threatening predator itself. By informing a predator that it has been detected, prey may be able to convince it to look for an easier catch elsewhere, and thereby deter its pursuit. While this verbal argument seems plausible, it is difficult to evaluate without a formal mathematical model. To this end, we use game theory to model a situation in which prey signal awareness to predators. We find that under certain conditions, alarm calls can indeed be honest signals directed to predators rather than warnings directed to conspecifics. This may explain behaviors such as tail-flagging in white-tailed deer, mobbing in some bird species, and vocal alarm calling in mammals. (Anti-predator Behavior, Tuesday 5:30 PM - 5:45 PM, NMM2)

30 People petting cats: a complex interaction

Penny L. Bernstein*

Kent University - Stark Campus (pbernstein@stark.kent.edu)

It is estimated that over 60 million cats currently reside as pets in the United States. Yet few studies have focused on how cats and people interact in the home setting. This preliminary study examines the petting interaction. Using surveys of cat owners, I sought to identify what body areas owners perceived as being the preferred targets of their cats, and owner perceptions of how their cats solicited petting from them. Analysis of data for 90 cats in single-cat homes provided few surprises; results reflected patterns that are familiar to any cat owner. For example, owners perceived a range of body areas (about 7) their cats preferred for petting, from the "Dorsal head region: cheeks, top of head, nose/face" through "Base of the tail" to "No preference, pet anywhere". Gender of the cat seemed to play a role in preferences. Solicitation behaviors were also familiar, and "rubbing" (of legs, hands, etc) was the most frequently cited. Meowing and jumping on laps were also cited frequently and purring, flopping on the ground nearby, sitting and looking at or walking by, stopping, and looking back, were cited less frequently. The most interesting result that owner descriptions provided, however, was a realization that the petting interaction is quite complex, and definitely two-way. Either the cat or the owner may initiate petting, resulting in a petting bout or a rebuff by either party. Misreadings by either party can also occur. I intend to undertake video-taping of naturally-occurring petting interactions in the future. (Regular Poster Session, Tuesday evening, Gym)

31 Cross-fostering alters adult patterns of aggression in Peromyscus mice

Janet K. Bester-Meredith* & Catherine A. Marler

University of Wisconsin (jkbester@students.wisc.edu)

Early developmental experiences can produce a cascade of effects on adult behavior. To determine how changes in parental behavior alter social behavior in offspring, we examined the effects of cross-fostering on aggression in two Peromyscus species. Previously we showed that unmated male California mice (P. californicus) attack conspecific males rapidly in two types of aggression tests, the resident-intruder and neutral aggression tests. In contrast, male white-footed mice (P. leucopus) attack more slowly in these two tests. Cross-fostering alters these patterns of aggression by causing males from each species to resemble their foster parents in behavior. After cross-fostering, males from the less aggressive species, the white-footed mouse, show no change in the resident-intruder test and more aggression in the neutral aggression test. However, males from the more aggressive species, the California mouse, show a decrease in resident-intruder aggression and no change in neutral aggression. These behavioral changes in cross-fostered white-footed mice are associated with body weight during development and the amount of parental behavior shown by foster parents. These results suggest that the quality of care shown by parents produces changes in social behavior that last through adulthood. (Learning of Social Signals, Sunday 5:15 PM - 5:30 PM, NMM1)

32 Evidence for male mate-choice as a mechanism of population discrimination Ahrash N. Bissell* & Emilia P Martins University of Oregon (abissell@darkwing.uoregon.edu)

How do similar species avoid interbreeding with each other? One possible mechanism is that the species can tell each other apart and simply avoid each other. Similarly, it is possible that populations (within a species) may be able to discriminate each other and avoid interbreeding. If this scenario is correct, then the discrimination seen at the population level may be the beginning stages of the discrimination seen at the species level. Typically, especially in sexually-dimorphic species, the mechanism of discrimination is assumed to involve female-choice or male-male competition, though this assumption is largely untested in many organisms. In this study, we used several populations of Sagebrush lizards (Sceloporus graciosus) to examine whether the populations can tell each other apart. Specifically, we asked whether population-level discrimination is more apparent in same-sex or opposite-sex interactions, and whether discrimination takes the form of attraction or avoidance. We found that the lizards can tell different populations apart. Surprisingly, we found that males prefer females from their own population, whereas female-choice and male-male competition were less apparent. Thus, it seems that male preferences may play an important role in mate-choice and population differentiation. (Recognition & Mate Choice, Tuesday 2:45 PM - 3:00 PM, NMM1)

35 Stabilimenta in spider webs: predator-prey conflict and sensory drive

Todd Blackledge*

Ohio State University (blackledge.8@osu.edu)

Signals can evolve through a process termed sensory drive where biases in sensory physiologies of receivers direct the evolution of signal form. Sensory drive is a major contributor to the diversity of sexual signals but little is known about its role in the evolution of sensory cues under natural selection. I investigated the role of stabilimenta, conspicuous designs of bright silk in spider webs, as possible predator defenses or prey attractants. I found that stabilimenta are significantly associated with the ability of spiders to defend themselves against predatory wasps but that spiders incur a 34% reduction in their own prey capture when they include stabilimenta in their webs. This predator-prey conflict appears to have played an integral role in the evolution of the color properties of spider silks. I found that stabilimentum silk is cryptically colored to the insect prey of spiders, unlike more primitive silks. This supports an hypothesis that the color properties of spider silk have evolved under sensory drive from the visual systems of insect prey. My data demonstrate the wider applicability of sensory drive to systems evolving under natural selection but also caution that it can have novel effects such as the evolution of cryptic, rather than conspicuous, visual cues. (W.C. Allee Competition, Monday 10:45 AM - 11:00 AM, Sale)

36 Automated recognition of cetacean vocalizations in noise: Analysis of response time in studies of hearing.

Diane Joyner Blackwood*

Texas A&M University (blackwood@cls.org)

A non-invasive technique for discovering some aspects of animal cognition is through the use of reaction time data. When observers score acquired data to find reaction times, though, unwanted bias can be inserted. In order to aid both data collection and data analysis, an algorithm was designed and implemented that finds vocal responses made by bottlenose dolphins and white whales (Tursiops truncatus and Delphinapterus leucas, respectively). The algorithm was tested against human-scored response data, and achieves a 98% match to human scoring. Because the algorithm makes the decision processes objective and parametric, much of the potential for observer bias can be eliminated. Hearing tests are similar to those for humans where the subject responds whenever they hear a test tone and the intensity is increased and decreased accordingly. In hearing tests, using a stair-step method of finding thresholds, analysis shows that response times are faster and length of the response is longer for louder tones for some frequencies tested. (Communication 1, Wednesday 10:15 AM - 10:30 AM, NMM1)

38 Sexual dietary partitioning in river otters: Dimorphism or cooperative foraging?

Gail M. Blundell*, Merav Ben-David & R. Terry Bowyer

University of Alaska - Fairbanks & Institute of Arctic Biology (ftgmb@uaf.edu)

Why do males and females in some species eat different diets (i.e. sexual dietary partitioning)? In many cases, dietary differences between genders can be attributed to differences in body sizes (i.e., sexual dimorphism). Generally if dimorphism occurs, males are usually bigger than females. Larger body size may confer superior competitive abilities for males, allowing them access to better quality diets. Alternatively, males may need to eat more or different diets because they have greater energetic demands than do females because they are larger. We hypothesized that social organization in coastal river otters (Lontra canadensis) was related to sexual dietary partitioning. We radio-tracked 55 otters in Prince William Sound, Alaska, from 1996 to 1998 to determine their social organization. We also used stable isotope analysis of hair samples from 111 individuals to determine what otters eat. We found that males preyed more on rapidly-swimming pelagic fishes, whereas females consumed more sedentary, intertidal fishes, which constitute a lower-quality diet. Subtle sexual dimorphism (males were only an average of 10.8% larger than females) may enable males to swim better and thereby capture faster prey, but we believe that sociality plays a key role in these dietary differences between the genders. Only 53% of the females that we radio-tracked were social, occurring mostly in mixed-gender groups outside of mating season, whereas 76% of males were social, travelling mostly in all-male groups. Because females were most often social with males, we excluded gender from further analyses and evaluated diets of otters with respect to sociality. We discovered that otters that were more social had diets significantly higher in pelagic fishes. We hypothesized that social otters were working together to capture schooling pelagic fishes (i.e., cooperatively foraging) and therefore would be more efficient at foraging than an otter that was hunting alone. Thus social otters should require less space in which to meet their energetic needs. Our radio-tracking data revealed that highly social otters used less space (i.e., had smaller home ranges) than did less social otters, and otters that foraged alone had the largest home ranges. We suggest that the time-consuming task of raising offspring prevents females from joining mixed-gender groups, but when not raising young, females join males to cooperatively forage for better-quality prey that would be more difficult to acquire as a solitary forager. (Social Behavior 1, Monday 2:45 PM - 3:00 PM, NMM2)

40 The Effects of Attenuated Courtship on Parental Care in a Monogamous Species

Angela Bockelman* & Murray Itzkowitz

Lehigh University (akk4@lehigh.edu)

Courtship behavior is often considered in the context of mate selection. However, few studies investigate the role of courtship as it pertains to parental care in monogamous species. Courtship in monogamous species can be quite long, and often includes repetitive behaviors that are similar to those used in offspring care. This repetition may be an attempt to synchronize their parental care activities. Shortened courtship should then affect the parents' abilities to coordinate offspring care activities. To investigate this, we shortened courtship in the monogamous, biparental convict cichlid Archocentrus nigrofasciatum, and examined the subsequent parental behavior. Our results indicate that while courtship is not necessary to synchronize egg laying and fertilization, it may be crucial in the synchronization of offspring care activities. (Regular Poster Session, Tuesday evening, Gym)

42 Differential Response of Pacific Harbor Seals (Phoca vitulina richardsi) Towards Kayaks Compared to Other Watercraft

Amy S. Bohorquez*, Michael J Galloway, Deborah E Green, Emma K Grigg, Sarah G Allen & Hal Markowitz

San Francisco State University & Point Reyes National Seashore (amysb@sfsu.edu)

Previous studies have considered the effects of various types of watercraft disturbances on the haul-out patterns and behavioral responses of harbor seals. We considered the variation in occurrence of kayaks within 200m in comparison with other types of watercraft at two harbor seal haul-out sites within San Francisco Bay, California. Since kayaks are more maneuverable they often advance closer to the haul out site than other types of watercraft. A higher proportion of kayaks elicit a disturbance response from the seals than all other types of watercraft within 200m of the haul-out sites. Kayaks within 200m also caused a higher proportion of flushes. This differential response to the kayaks is a consequence of the proximity of the kayaks to the seals. Kayaks are more likely to elicit disturbance responses from hauled-out harbor seals because they are quiet and low to the water. These factors may not allow the seals to detect kayaks until they are much closer to the haul-out site and may lead to a higher startle response. (Applied Animal Behavior, Tuesday 2:15 PM - 2:30 PM, Sale)

43 Visual discrimination learning in a carnivorous marsupial, the Fat-tailed dunnart (Sminthopsis crassicaudata)

Kathryn R. Bonney* & Clive D.L. Wynne

University of Western Australia (kathryn@psy.uwa.edu.au)

Marsupials are an unusual group of animals that have, until recently, been considered primitive and unintelligent. Research on a species of carnivorous marsupial, the Fat-tailed Dunnart, challenges this view. On tests of visual discrimination learning (where animals were trained to approach one of two visual stimuli for food), the dunnarts' performance showed, after several tasks, instances of one-trial learning, where a new task is learned after the minimum number of mistakes. This is also a feature of primate learning, but rarely seen in other groups of mammals. The learning skills of dunnarts could be an adaptation to predatory life in the desert, where food is sparse and rapid learning and search strategies would be useful to efficiently exploit their environment. (Animal Learning & Cognition, Tuesday 9:30 AM - 9:45 AM, Sale)

46 Influence of demography, helpers, and landscape on variation in individual dispersal patterns in Florida scrub-jays.

Reed Bowman* & Nathalie J. Hamel

Archbold Biological Station (rbowman@archbold-station.org)

Variation in individual dispersal patterns in cooperative breeding birds may be influenced by the intrinsic benefits of delaying dispersal and the extrinsic constraints on finding high-quality breeding opportunities. Intrinsic benefits may vary little among populations but variation in extrinsic constraints, such as demography, population density and spatial patterns, and landscape patterns that influence movements, may vary greatly. In particular, habitat fragmentation is likely to influence many of these extrinsic constraints. Occupied patches in fragmented systems may vary in habitat quality that influences survival and reproductive rates, the number of territories within patches, the number, size, and distance to other occupied patches, and the landscape mosaic between occupied patches; thus the relative costs and benefits of different dispersal strategies may vary among patches. We compared dispersal patterns of Florida scrub-jays in contiguous and fragmented habitat and attempted to explain variation in individual dispersal patterns. Individual dispersal patterns varied relative to the expected patch-specific costs and benefits. (Dispersal Symposium, Sunday 11:30 AM - 11:45 AM, Sale)

47 Sexual Selected Characters, Life History Traits, and Antagonistic Pleiotropy

La Roy Brandt*

University of Kansas (Lbrandt@falcon.cc.ukans.edu)

Genetic variation is required for evolution to occur. One of the most misunderstood concepts of evolution is how variation can be maintained within a population. It is suspected that genetic trade-offs could be a mechanism that maintains, at least in part, genetic variability. Using a breeding experiment of half- and full-siblings, genetic trade-offs were determined between three characters under female choice and three other life history traits in the lesser wax moth, Achroia grisella. Attractive male moths do not live as long as relatively unattractive moths and do not spend as much time signaling to attract a mate. Such trade-offs have been theoretically suspected but have never been empirically demonstrated. These results shed new light on the theory of the maintenance of genetic variation. (Sexual Selection, Sunday 3:45 PM - 4:00 PM, NMM2)

48 Mate choice: a possible mechanism for a moving avian hybrid zone

C.L. Bronson, Thomas C. Grubb, Jr.* & Michael J. Braun

Ohio State University & Smithsonian Institution (bronson.5@osu.edu)

Carolina (Poecile carolinensis; CACH) and black-capped (P. atricapillus; BCCH) chickadees hybridize in an east-west band across northern Ohio. Within the past century, this hybrid zone and the CACH range to the south have been moving northward into the retracting BCCH range. We examined one possible mechanism for this shift in distributions, namely mate choice in females of both species. Given a choice within an aviary setting, a significant majority of females of both species that had not observed social interactions between a male CACH and a male BCCH preferred to associate with the BCCH male. In nature, both species form consexual dominance hierarchies, often correlated with body size. In the aviary, CACH males dominated BCCH males unless a CACH male was substantially smaller. Once females of both species had observed the dominance relation between a particular dyad of CACH and BCCH males, they associated preferentially with the dominant male, regardless of species. Thus, male CACH dominance may be contributing to the northward movement of the hybrid zone. (Mate Choice 3, Monday 3:15 PM - 3:30 PM, NMM1)

49 Brown capuchin monkey's understanding of their partner's role in exchange

Sarah F. Brosnan* & Frans de Waal

Yerkes Regional Primate Research Center & Emory University (sbrosna@emory.edu) The exchange of material goods, such as food, would add to the repertoire of reciprocal interactions in a species. The ability to exchange has been demonstrated in apes, but has not been rigorously tested in any monkey species. Brown capuchin monkeys, Cebus apella, are highly intelligent and known to cooperate and share food, which makes them ideal candidates. This study aimed to 1) train capuchin monkeys on an exchange task, and 2) determine if the monkey recognized the need for a partner in these interactions. Tests were conducted using socially housed capuchin monkeys isolated in a familiar test chamber. Monkeys exchanged a non-edible item for a food reward with a human exchanger. Individuals were categorized as either 'fast' learners of the exchange task (minimal or no shaping required) or 'slow' learners (extensive shaping required). Then tests were done to see if the monkeys recognized the necessity of an exchange partner to receive the reward and to see if the monkeys recognized one individual of two as the exchange partner. We found differences in both the speed of acquisition and their understanding of the human's role. (Social Behavior 1, Monday 4:15 PM - 4:30 PM, NMM2)

54 Comparisons of prey choice and chemosensory prey preference in adult and neonatal garter snakes.

Gordon M. Burghardt*

University of Tennessee (gburghar@UTK.edu)

Diet and genetics interact in determining the ontogenetic trajectory of chemosensory and prey preferences in the common garter snake, Thamnophis sirtalis, a dietary generalist. Adult snakes were captured from a single small field in an earthworm ingesting population of snakes. The snakes were maintained in captivity until they gave birth. Adult (n = 18) and neonatal snakes (n = 86) were given similar prey chemical tests on several concentrations of earthworm and fish surface substance extracts. In spite of being fed fish frequently in captivity, adult snakes were more responsive to earthworm cues and earthworm prey. For neonates, initial responses to chemical cues from fish and worm were similar. After 12 meals on fish, the neonates preferred fish in both prey choice and chemosensory responses and growth rates were related to changes in chemoreceptive responses. Lifelong diet may reduce plasticity and the ability of dietary experience to alter prey preference. Alternative explanations and possible physiological mechanisms will be discussed. (Predator Prey, Monday 2:00 PM - 2:15 PM, NMM2)

55 Mass and habitat-dependent escape ability of migrating Calidrine sandpipers

James G. Burns* & Ronald C. Ydenberg

Simon Fraser University (jgburns@sfu.ca)

The effect that predatory falcons have on the way birds migrate has just begun to be investigated. What was long considered a just a necessary fuel for migration, fat, may also cost the prey birds because it affects their ability to escape predators. Fat is the primary fuel used in long migratory flights, but is believed to slow a bird's escape ability because of extra weight. We tested for the effect of fat on escape ability in three species of migrating sandpipers. A bird's escape ability may also depend on how risky the habitat it prefers is. We tested for how species differ in their ability to escape predators, and what these differences are caused by. (Anti-predator Behavior, Tuesday 4:15 PM - 4:30 PM, NMM2)

56 Seed exploitation by the Rice Weevil, Sitophilus oryzae

James F. Campbell*

USDA ARS (campbell@usgmrl.ksu.edu)

The fitness of insects whose immature stages feed inside a single seed is strongly influenced by the oviposition decisions of females. The Rice Weevil, Sitophilus oryzae, is a seed parasite and can be is a major pest of stored grains such as wheat and rice. Females chew a hole into the seed, lay an egg, and fill the hole with an egg plug. Larvae must then complete development within the seed selected by the female. Fitness was influenced by the size of the seed, where the egg was deposited, and how many other eggs are deposited. The seed size threshold for oviposition varies among individuals and is influenced by experience. The number of eggs deposited in a seed increases with seed size, even though most of the additional eggs laid will not emerge. (Regular Poster Session, Tuesday evening, Gym)

58 The role of the conspicuous Display exhibited by Volatinia jacarina males (Emberizidae) in reproduction

Carlos B. Carvalho*, Regina H. Macedo & Verônica M. Borges

Universidade de Brasília (humming@unb.br)

The concept of sexual selection is useful to explain the evolution of characteristics such as male displays that could help some individuals obtain a greater number of sexual mates. The blue-black grassquit (Volatinia jacarina: Emberizidae), is a small, granivorous, neotropical bird that is very abundant in Brazil. The males of this species exhibit a distinctive display that consists of repeated vertical flights from elevated perches. During these leaps they expose the white underwings and emit a short buzzing vocalization. The males usually display in clusters, a pattern that overall is quite similar to that exhibited by lekking species; however, information about the species’ mating system is still scarce and controversial. The study was carried out through field observations during the species’ reproductive season in the cerrado region of Central Brazil. Preliminary results will be discussed, and include the differential ability of males to attract females, given the characteristics of their displays (height and rate of flights), size and structure of territories, and morphological factors. Additional information concerns males’ nesting success and paternal investment. (Regular Poster Session, Tuesday evening, Gym)

59 First-time song learning in adult starlings

MarthaLeah Chaiken*

Rutgers University - Newark (chaiken@andromeda.rutgers.edu)

No matter how old you are, you can probably learn a second language well enough to ask a question, use the past tense, or form a relative clause. But it would be a different story if you tried to learn a first language as an adult. Current research suggests that you could never master such grammatical feats. The present study is designed to see if the situation is similar when birds are learning to sing. Songbirds are among the few animals that, like humans, learn their vocal signals by imitation. Some birds, like zebra finches, learn only songs they hear during a specific period, usually just after leaving the nest, and they sing these same songs for the rest of their lives. Other birds, like starlings, can learn new songs as adults. But can starlings learn to sing for the first time as adults? The question is of interest to neuroscientists who study songbirds to identify mechanisms that permit and limit learning. To find the answer, I collected young starlings from the nest and raised them by hand. For the ensuing year, they never heard another bird sing. When they reached maturity, their songs were garbled, nothing like the highly structured songs of normal starlings. Each bird was then housed with a wild-caught adult male starling throughout the winter and early spring. By the end of their second year, the hand-reared birds had imitated their wild-caught companions and were singing normal songs. Thus it appears that first-time song learning, unlike language learning, can take place at any age. (Learning of Social Signals, Sunday 3:45 PM - 4:00 PM, NMM1)

60 Seasonal changes in activity areas of Southern Plains Woodrats (Neotoma micropus)

Jesus A. Chavez, Jr.* & Diane M. Post

University of Texas - Permian Basin (chuchi@caprok.net)

Our study analyzed differences in the activity area of male and female Southern Plains woodrat (Neotoma micropus) during spring breeding and fall cashing periods. The study was conducted in the mesquite grasslands of West Texas. Activity areas were determined by use of fluorescent dye powder. Our results indicate that males have a higher activity area in the spring than in the fall. The increase is probably due to mate search activity. Female activity areas tend to be larger in the fall. The increase may be due to the fact that females must cache food for themselves and young who, over the winter, are in the same den. (Regular Poster Session, Tuesday evening, Gym)

61 Vocal Behavior and Conservation in Wild African Grey Parrots

Janine R. Clemmons*

University of Wisconsin (jrclemmo@facstaff.wisc.edu)

One of the hallmarks of human behavior that distinguishes us from other species is our ability to imitate the behavior of one person (our grandmother or friend, for example) and then pass along that behavior to other people of diverse ages and relationships. Imitation is rarely observed in wild animals with the exception of certain species of birds who learn how to perform songs from their fathers or members of a neighborhood. One of the most renowned bird imitators is the African Grey Parrot. But are its abilities to imitate used in its own bird societies, or is imitation an unnatural kind of behavior that occurs only with captive parrots? A population of African Grey Parrot that may be the only wild population capable of helping to answer this question is imperiled. I discuss how the scientific quest on the evolution of culture and the conservation quest to preserve a rare and valuable form of behavioral diversity merge into a mutually dependent partnership. (Conservation, Wednesday 9:45 AM - 10:00 AM, Sale)

67 Female mate choice predicts future male traits

Ellen S. Davis*

University of Wisconsin - Madison (esdavis@facstaff.wisc.edu)

Many studies on mate choice in waterfowl indicate that female mate preference is best predicted by male courtship activity. However, courtship and pair-formation typically occur weeks or months prior to the breeding season, which is when fitness is realized. Sperm aside, in many seasonally monogamous waterfowl species the only contribution males make to the breeding effort is mate guarding. The most demonstrable effect of mate guarding in waterfowl is to increase female foraging efficiency, which in turn increases her reproductive output. Male mate guarding has also been shown to be under the influence of testosterone (T) in some passerine species. In this study on captive mallards my results indicate that fall female mate choice predicts, but does not affect, spring T levels in males. Moreover, high T males were more effective at guarding their mates than low T males. Taken together, these results indicate that females are choosing males during the fall who will guard them effectively during the spring. This study is the first to link fall mate choice to possible fitness benefits realized during the spring breeding season. (Mate Choice 2, Sunday 1:30 PM - 1:45 PM, NMM2)

68 Burrow dispersal in ghost crabs

Jessica M Davisson* & Mary L. Crowe

Coastal Carolina University (crowe@coastal.edu)

Ghost crabs live in burrows on sandy beaches along the Atlantic ocean. The burrows crabs live in are not randomly distributed; rather juvenile burrows are more likely to be found near the water while adult burrows are found above the high tide line. The foredune area is devoid of burrows. A variety of abiotic and biotic factors may influence burrow dispersal. In this study we examined the effect that sand moisture content and grain size play on burrow location. Preliminary results show that sand collected from 30 m from had a higher moisture content than the other three distances. It appears that sand collected from the top and bottom of the cores do not differ in sand moisture content. Grain size analysis has just begun and these results will be presented. (Regular Poster Session, Tuesday evening, Gym)

69 Diet Self-selection increases food hoarding and food intake in pregnant Siberian hamsters (Phodopus sungorus)

Diane E. Day*, Eric M. Mintz & Timothy J. Bartness

Georgia State University (gs08ded@panther.gsu.edu)

Siberian hamsters increase food intake and food hoarding during pregnancy simultaneous with marked reductions in body fat. We employed the diet self-selection model (‘dietary wisdom’) in an attempt to obtain insight into which changes in energy metabolism during gestation and lactation preparation might trigger increases in food hoarding. Therefore, we asked: How does diet self-selection affect the normal pregnancy-induced increases in body mass, food intake and food hoarding? This was accomplished using a simulated burrow system and a pellet chow (PC) versus a self-selected diet composed of sunflower seeds (SS), rabbit chow (RC) and PC. Pregnant hamsters self-selecting their diet increased food hoard size, food intake, and body mass compared with pregnant hamsters fed only PC, or compared with their virgin counterparts (except that food intake was not increased). Pregnant hamsters fed only PC increased food hoard size, food intake, and body mass compared with their virgin counterparts. These results suggest that diet self-selection exaggerates food intake, food hoarding and body mass in both pregnant and virgin Siberian hamsters.

(Regular Poster Session, Tuesday evening, Gym)

70 Environmental correlates of vocal communication of wild pygmy marmosets

Stella A. de la Torre*

Ministerio de Turismo y Ambiente (sdelat@yahoo.com)

The acoustic characteristics of the habitats of two wild populations of the pygmy marmoset, Cebuella pygmaea, in Amazonian Ecuador were quantified to evaluate the effects of habitat acoustics on the vocal signal structure and vocal behavior of the species. Measures of ambient noise, sound attenuation and reverberation were obtained through recordings and broadcasts of pure tones and pulse trains. Data on context, vocalization rates and acoustic analyses of four vocalizations types were obtained from six groups of pygmy marmosets, three from each population, in both the dry and rainy seasons. Despite gross similarities in the estimated vegetation structure, habitats differed in their acoustic characteristics. The calls of pygmy marmosets had frequencies that coincided with relatively quiet regions of the ambient noise spectra of the habitats. Spectrographic analyses of the vocalizations showed inter-population differences in the temporal and frequency variables of Trills, J calls and Long calls. Some of these differences appear to be related to differences in habitat acoustics. Evidences for significant interpopulation differences in primate species are fairly scarce; aside from studies of pant-hoots in chimpanzees, this study is the first to show variation in natural call structure across populations in nonhuman primates. Research supported by NGS Grant 5806-96. (W.C. Allee Competition, Monday 11:15 AM - 11:30 AM, Sale)

73 An experimental study of deception in ringtailed lemurs

Robert O. Deaner*

Duke University (rod1@acpub.duke.edu)

Because of their social and ecological similarities, ringtailed lemurs and cercopithecine monkeys have long been compared. One difference is that cercopithecines have been observed to deceive their groupmates but ringtailed lemurs have not. This difference may due to observational bias, differential opportunities for deception, or a difference in social cognition. In order to distinguish among these possibilities, I presented opportunities for ringtailed lemurs to deceive each other in the 'Menzel' paradigm. Here a subordinate animal is informed of a favored food's location, and then the informed subordinate and an uninformed dominant are simultaneously released into an enclosure. Previous work has shown that an informed mangabey can learn to consistently lead an uninformed dominant away from the food (i.e. deception), thereby increasing its own food intake. Two male and two female lemurs were initially trained to use a visual signal to find food at one of eight feeding sites in an outdoor enclosure. During experimental trials, an informed male was simultaneously released with an uninformed dominant female. The following results were obtained. First, females usually followed males to baited food sites and monopolized the food. Second, after consistently moving directly to the food and losing it to the female, males employed alternative tactics. Third, some alternatives were effective (e.g. moving initially away from food and then towards it) but others were not (e.g. not moving towards any food site). Finally, unlike mangabeys, male ringtailed lemurs did not consistently employ effective alternative tactics (i.e. use deception). These results are consistent with the hypothesis of a cross-species difference in social cognition.

(Behavioral Context, Monday 11:30 AM - 11:45 AM, NMM2)

76 Parasitic infection and spatial learning in CD-1 male mice

Shirley A. DesRosiers* & M. E. Rau

McGill University (shirley.desrosiers@sympatico.ca)

It has been suggested that low intensity infections with the intestinal nematode, Heligmosomoides polygyrus, can decrease the ability of mice to learn spatial tasks in a laboratory setting. In the field, decreased learning ability due to infection may have a vast array of detrimental consequences. Thus, in order to assess the impact of infection on behavior, male CD-1 mice were subclinically infected with 100 L3 H. polygyrus larvae and tested in a Morris Water Maze. The results indicate that all groups learned the task (P<0.0001), but that a moderate primary infection failed to alter the capacity of the mice to learn a given spatial task. (Animal Learning & Cognition, Tuesday 10:30 AM - 10:45 AM, Sale)

78 Novel metrics for comparison and use of dominance matrices

Brad Dickey*, Robert E. Ziemba & Philip H. Crowley

University of Kentucky (myrmeleon@hotmail.com)

The outcomes of aggressive social encounters - which individuals win fights, have important consequences for animals that live in groups. In published papers that deal with aggressive behaviors, the data on wins and losses among group members are often displayed in a table and the patterns of entries are described verbally. For instance if one animal dominates all other animals in the group, most wins are clustered at the top of the table and the group is described as 'despotic'. There are few numerical indices that describe the patterns mathematically. We require such indices to test if the patterns are real or if they could be the result of random chance. Furthermore, to understand social behaviors better we need to be able to determine the response of the group to environmental changes: by observing how indices change when food levels or the size of the group varies, we can better understand how groups function and how the individual animals are affected by different social dynamics. We have developed indices to describe and test these patterns of social interactions, such as despotism, and these indices will be described and explained using real and simulated data. (Social Behavior 1, Monday 5:30 PM - 5:45 PM, NMM2)

83 Variability in resource-based behavior of the Threespine Stickleback (Gasterosteus aculeatus) in Iceland

Lisa I. Doucette*, Skúli Skúlason, & Sigurdur S Snorrason

Hólar College & University of Iceland (lisa@krokur.is)

Icelandic freshwater systems are geologically young and have been colonized in the last 10,000 years. Due to the isolation of the country only five species of freshwater fish are found. These few species of fish can choose between a variety of habitats and food resources, for which competition from other fishes is very low. Such conditions can lead to new behavior strategies as the existing fish species adapt their behavior to take over unoccupied habitats. Seven groups of Icelandic sticklebacks were tested and found to differ in feeding, schooling, and predator avoidance behaviors. Differences in feeding behaviors correspond to observed differences in the mouth shape of these groups of fish. Thus, as fish adapt their behavior to capture new prey types, a specialization of their mouth shape may soon follow. Differences in predator avoidance behaviors indicate that predation may, at least in some cases, be a driving force in maintaining separate groups within a lake. These results suggest that Icelandic sticklebacks are evolving behavioral adaptations that may lead to differences in physical appearance, and could eventually lead to the evolution of a new species. (Social Behavior 1, Monday 4:00 PM - 4:15 PM, NMM2)

86 Song Predicts Cell-mediated and Humoral Immunity in European Starlings

Deborah L. Duffy*

Johns Hopkins University (dduffy@jhu.edu)

For nearly twenty years, ecologists have been investigating the relationship between reproductive success and disease resistance. One idea that has been gaining attention recently proposes that elaborate ornamentation in males, such as plumage or song, is indicative of their ability to mount an immune response (immunocompetence). During the breeding season, males advertise their health and vigor to females through the development of elaborate traits, often mediated by testosterone which has been demonstrated to suppress immunity in some species. Therefore, only the most immunocompetent males are able to bear the cost of high testosterone concentrations and thus attract more mates. In these studies, I investigated the relationships among song, testosterone, and immunity in a songbird, European starlings (Sturnus vulgaris). Administration of testosterone to male and female starlings resulted in reduced responses of two components of the immune system, cell-mediated and humoral, following inoculation with harmless substances. Furthermore, behavioural observations revealed that males who produced more song exhibited enhanced cell-mediated and humoral immunity than those who rarely sang. Therefore, as the first to use direct assessment of these two components of immunity, these studies provide conclusive evidence that song predicts immunocompetence in starlings and that this relationship may be mediated by testosterone. (W.C. Allee Competition, Monday 11:30 AM - 11:45 AM, Sale)

87 Mate copying in humans

Lee A. Dugatkin*

University of Louisville (laduga01@athena.louisville.edu)

We examine whether male and female undergraduates copy the mate choice of others. Study 1 demonstrated that peer attention increased both short-term and long-term mating interest and that females were more influenced than males by levels of peer attention. In addition, females were more likely than males to perceive that the target who received high peer attention was also wealthy. Study 2 was designed to disentangle the impact of peer attention and wealth. While perceived wealth did influence popularity per se, it was not a particularly strong predictor with respect to mate copying, when compared to other factors such as humor and, more generally, a pleasing personality. (Learning of Social Signals, Sunday 5:00 PM - 5:15 PM, NMM1)

93 Juvenile hormone increases prior to foraging in the Honey Bee, Apis mellifera

Michelle M. Elekonich*, David J. Schulz, Guy Bloch & Gene E. Robinson

University of Illinois - Urbana-Champaign (elekonic@life.uiuc.edu)

Worker honey bees begin their adult lives working in the dark inside the hive. At about 3 weeks of age they become foragers and begin collecting nectar and pollen at flowers. Juvenile hormone (JH) is one of the principal developmental hormones in insects. Foragers have higher circulating levels of JH than bees working in the hive. We wanted to know if JH increased before the bees became foragers, or if it increased due to foraging experience or diurnal changes in response to exposure to sunlight. We placed colonies made completely of young non-foraging bees into a large outdoor flight cage and recorded all their foraging trips. We measured hormone levels in foragers on their first foraging flight, in foragers with little experience, and in foragers with a lot of experience. We also measured hormone levels in bees working inside the hive, because it was known previously that they have levels lower than foragers. We found that foragers with different amounts of experience all had similar levels of JH, but all the foragers had higher hormone levels than the bees working inside the hive. We also sampled other foragers every six hours around the clock. We found that juvenile hormone exhibits a daily cycle in foragers, with high hormone levels in the middle of the night and low levels in the early morning. Our results suggest that JH increases in anticipation of foraging behavior and levels of JH are modulated in a daily fashion. These data suggest that the transition from hive worker to forager is due to internal developmental processes rather than the result of experience. In many animal species hormones exhibit daily cycles which can serve to coordinate the timing of developmental processes with the necessary changes in behavioral state. Cyclical changes in worker JH may act in a similar fashion. (Regular Poster Session, Tuesday evening, Gym)

94 Multi-channel digital acquisition methods applied to simultaneous acoustic and physiological events

Wesley R. Elsberry*, Donald A. Carder, Ted W. Cranford, Jennifer A. Carr & Sam H. Ridgway

Texas A&M University, U.S. Navy Marine Mammal Program & Science Applications International Corporation (welsberr@inia.cls.org)

Dolphins utilize click vocalizations for both biosonar and communication. We have trained dolphins to allow us to place pressure catheters in the nasal passages to discover the mechanism of sound production and the relationships between pressure in the nasal passages and acoustic energy output by the dolphins. In order to do this, we developed a custom data acquisition system with significant advances in convenience and capabilities. A high-bandwidth digital system captures both acoustic and physiological measures simultaneously on the same system, eliminating synchronization issues between multiple recording devices and yielding digital data for analysis without the need to digitize from analog tape data recorders. Up to eight total channels of data can be recorded, while saving half the bandwidth of the data acquisition card for the acoustic data. This research represents the first time that intranasal pressure recordings have been made at the same time as acoustic recordings while a bottlenose dolphin (Tursiops truncatus) performed a biosonar task. (Regular Poster Session, Tuesday evening, Gym)

96 Variations in foraging behaviors of predatory mites

Jia Fengyou*

Kansas State University (fjia@oz.oznet.ksu.edu)

Response of predators to prey-induced plant volatiles can affect the length of time a predator spends in a prey patch and the probability of a predator finding a new prey patch. Variation in response to prey-induced plant volatiles may lead to different foraging decisions, thereby changing both within-patch dynamics and between-patch dispersal. We found significant phenotypic variation in two behavioral assays of response to prey-induced plant volatiles among inbred lines of the predatory mite, Phytoseiulus persimilis. In wind-tunnel tests to measure residence time, female adult predators from certain lines left prey patches sooner than others when a distant source of prey-induced plant volatiles was present; there was no difference in leaving rate when no source was present. In a measure of reactive distance, the same lines that were more likely to leave in the wind-tunnel in the presence of volatiles were also more likely to find an odor source (i.e. prey patch) from a distance on an arena. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

97 An association exists between mating system and length of time that meadow voles and prairie voles respond preferentially to the top-scent donor of an over-mark

Michael H. Ferkin*, Stuart T. Leonard, Kim Bartos, & Michelle K. Schmick

University of Memphis (mhferkin@memphis.edu)

Scent over-marking occurs when one individual places its scent mark on top of one deposited by a conspecific. This study determines the length of time voles in two different mating systems maintain a preference for the top-scent donor of an over-mark. Experiment 1 tested the hypothesis that the preference for the top-scent mark over the bottom-scent mark is longer in a meadow voles, Microtus pennsylvanicus, a non-monogamous species, relative to prairie voles, Microtus ochrogaster, a monogamous species. The data supported the hypothesis in that a preference for the top-scent mark was maintained for 48 h in male and females meadow voles, 24 h for male prairie voles, and only 12 h for female prairie voles. Experiment 2 tested whether pair-bonded prairie voles maintain a preference for their mate's scent mark for a shorter length of time if it is the top-scent mark than if it is the bottom-scent mark. The data did not support the hypothesis, but the data did match those gathered for prairie voles in experiment 1. Overall, the findings of this study suggest that a correlation may exist between mating system and the manner in which individuals respond to over-marks. (Mate Choice 2, Sunday 3:00 PM - 3:15 PM, NMM2)

99 What is sexy about field cricket courtship song?

Mark J. Fitzpatrick*, David A. Gray & William H. Cade

Brock University (mf94az@badger.ac.brocku.ca)

Much is known about calling song phonotaxis in field crickets. In the Texas trilling cricket, Gryllus texensis (formerly G. integer), females have a net stabilizing selection for the average male calling song. The courtship song is far less studied across all field crickets. We used G. texensis as a model to investigate if females show preferences for characters in the male courtship song. Both correlational and experimental trials have shown that females were selecting males using courtship song. Composed of two types of sound pulses, high frequency and low frequency ticks, females were selecting for shorter time intervals (silences) between the ticks - termed Gap 1. This gap was also correlated with male condition such that males with long silences were significantly in poor condition (light for their body size) when compared to males having short silences. Both Gap 1 and condition were repeatable, an indication of the amount of variation that can be attributed to consistency among males, suggesting a possible genetic basis. If heritable, females can increase the probability of mating with a genetically superior male by selecting against long Gap 1 durations - a potential example of the good genes model of selection. (Mate Choice 3, Monday 1:45 PM - 2:00 PM, NMM1)

100 Policing through conflict intervention: One mechanism by which stability is maintained in complex social systems?

Jessica C. Flack* & Frans de Waal

Emory University (jflack@emory.edu)

One question that arises in the study of animal societies is how stability is maintained in societies comprised of individuals with partially conflicting interests. Steve Frank (1995, 1996) phrased this question another way: how is competition among lower-level units suppressed in the formation of higher-level units? In order to investigate how individual behavior may contribute to overall conflict management, this study focused on how third parties react to and intervene in spontaneous agonistic interactions within a captive group of pigtail macaques (Macaca nemestrina). As predicted by Frank's model, the data suggest that when performed by individuals of high rank, certain types of intervention are associated with the termination and reduction of aggression, and with the facilitation of post-conflict affiliation between former opponents. We then asked what would happen to the operation of the pigtail social system if this behavioral mechanism by which conflict is managed was removed. The individuals performing most policing interventions were removed for one day every two weeks for twenty weeks. Data on rates, intensities, and complexity of conflicts, as well as on levels of social integration and reconciliation, were compared across two conditions: policing individuals present or absent. (Social Behavior 2, Tuesday 4:00 PM - 4:15 PM, NMM1)

102 The Role of Social Experience in Social Communication in Rhesus Monkeys

Sandra N. Ford*, Tanja Jovanovic, Michelle L. Tomaszycki, & Harold Gouzoules

Emory University (sford@learnlink.emory.edu)

In some primate species, agonistic recruitment is critical to both the development and maintenance of dominance relationships in the group, and screams appear to play a significant role in soliciting support from allies. Though monkeys are capable of producing these calls at birth, they appear to require experience to use screams in their proper context. In this case study, we observed and recorded the behavior and communication of a juvenile rhesus monkey, reintroduced into the group in which she was born, after being deprived of conspecific social experience for several years. She had spent most of this period alone, but was paired with an unrelated adult female from her group for several months before reintroduction. During aggressive encounters, the juvenile failed to respond in the same way as did her peers who were raised in the group. Despite the juvenile's inappropriate behavior, the female she had been temporarily housed with defended her during attacks; the juvenile’s reintroduction into the social group was, however, ultimately unsuccessful. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

103 Relationship between escape speed and flight distance in a wolf spider, Hogna carolinensis

Daniel R. Formanowicz, Jr. & Matthew K Nelson*

University of Texas - Arlington (kmnelson@uta.edu)

The relationship between running speed and flight distance is an important one in terms of escape from predators, especially in species that may have multiple defensive strategies. In the wolf spider, Lycosa carolinensis, the most obvious antipredator mechanism is flight. We examined the relationship between sprint speed and flight distance in wolf spiders by measuring sprint speed on a running track and, in a separate set of experiments with the same individual spiders, measured the distance at which they fled from an advancing model predator. Sprint speed was not significantly correlated with mass, size, or sex of the spiders. Sprint speed was significantly, positively correlated with flight distance. This correlation may be the result of a trade-off between two competing modes of antipredator mechanisms: escape and crypsis. In individuals with higher sprint speeds, escape may be the more advantageous option. Slower individuals may have a greater chance of surviving an encounter with a predator simply by remaining still and relying on crypsis. (Anti-predator Behavior, Tuesday 4:30 PM - 4:45 PM, NMM2)

108 Social interaction and vocal convergence in Carolina chickadees.

Todd M. Freeberg* & Jeffrey R. Lucas

Purdue University (freeberg@bilbo.bio.purdue.edu)

Chickadees join new flocks in the fall months. One of the major vocal signals of chickadees -- the chick-a-dee call -- has been shown to vary acoustically across flocks, such that each flock might be thought of as having a "signature" chick-a-dee call. If chickadees join new flocks and each flock has its own variants of the chick-a-dee call, it suggests that these calls are modifiable. We tested this question, and asked whether social interaction between a flock "joiner" and its new flock mates was necessary for vocal changes in the joiner to result. In social flocks, all birds were housed together in the same large aviary; in isolation flocks, the joiner and members of its new flock were housed in the same room, but in individual cages. Playbacks of the calls of the joiner, as well as acoustic analyses, indicated that significant changes in the joiner's chick-a-dee calls occurred only in the social flock condition. These data suggest that social interaction is necessary for vocal changes to occur in chickadee flocks. (Learning of Social Signals, Sunday 4:15 PM - 4:30 PM, NMM1)

109 A comparative study of avian auditory brainstem responses

Todd M. Freeberg, Jeffrey R. Lucas*, Ananthanarayan Krishnan & Glenis Long

Purdue University (jlucas@bilbo.bio.purdue.edu)

We recorded the electrical brain responses to sounds in 5 bird species (downy woodpecker, white-breasted nuthatch, tufted titmouse, Carolina chickadee, and house sparrow). These species vary taxonomically and in several song features. Our preliminary results suggest that several brain characteristics correlate with vocal complexity. We gave the birds clicks at a variety of rates (30 to 140/sec). Nuthatches (the species with the overall least complicated song) were most strongly affected by an increase in click rate, although none of the species showed a marked rate effect, even at 140 clicks/sec. This is much better than human hearing. Similarly, the time required for the brain to respond to clicks was longest in nuthatches. While these differences could result from differences in auditory acuity, they could also result from differential responses to sound frequency. We are currently evaluating this possibility. Our preliminary results support the intriguing idea that properties of the auditory-brain pathway are related to the evolution of avian vocal complexity. (Evolution of Signals, Tuesday 11:00 AM - 11:15 AM, NMM1)

110 Concordant patterns between male color and lighting environment in bluefin killifish populations

Rebecca Fuller*

Florida State University (Fuller@neuro.fsu.edu)

For aquatic animals, the physical properties of water can easily affect which colors can be seen. Some colors can be filtered out, and this should affect which colors are used by animals for communication. In this study, I examined the relationship between the filtering properties of the water and male color patterns in the bluefin killifish. Male color patterns are polymorphic. Males can have blue, red, or yellow fins. I found more males with blue anal fins in populations with low UV/Blue transmissions. This means that blues will only be seen across very short distances such as when courting females or fighting with other males but will diminish over longer distances possibly reducing detection by predators. (Communication 1, Wednesday 9:45 AM - 10:00 AM, NMM1)

111 Geographic variation in reproductive character displacement in mate choice by sailfin mollies

Caitlin R. Gabor* & Michael J. Ryan

University of Texas - Austin (gabor@uts.cc.utexas.edu)

We measured male sailfin mollies, Poecilia latipinna, strength of preference to mate with females of the same species, or with Amazon mollies. Amazon mollies, P. formosa, are an all female species of livebearing fish. They reproduce by gynogenesis; they must co-exist and mate with males of another closely related species (usually the mollies, P. latipinna or P. mexicana). Mating induces egg development but the offspring are only related to the mother. We predicted that male sailfin mollies collected from populations where they co-exist with Amazon mollies (sympatric) would be selected to avoid mating with Amazon mollies because males would be wasting energy and sperm by mating with these females. Males from populations that do not co-exist with Amazon mollies (allopatric) would not avoid mating with these unfamiliar females. We compared mate preference between males from sympatric populations and males from allopatric populations. As predicted, male sailfin mollies from six sympatric populations showed greater strength of preference for sailfin molly females over Amazon mollies compared to males from five allopatric populations. These results provide strong evidence for reproductive character displacement, a hypothesis for the evolutionary change in mate choice behavior in sympatric populations compared to allopatric populations. (Mate Choice 3, Monday 2:15 PM - 2:30 PM, NMM1)

112 Differential Scanning between Male and Female Phoca vitulina richardsi Hauled-Out at Yerba Buena Island, California

Michael J Galloway*, Emma K Grigg, Deborah E Green, Hal Markowitz & Sarah G Allen

San Francisco State University & Point Reyes National Seashore (mjgallow@sfsu.edu)

Previous studies have shown conflicting results in scanning behavior between adult male and female harbor seals. Scanning refers to movements that increase the seal’s visual field. This study compares differences in scanning bouts by hauled-out seals at Yerba Buena Island, California (YBI) between October 1998 and September 1999. YBI is primarily utilized by males at all times of the year. Up to three seals at different locations of the site were selected. Seal behavior was recorded for 15 seconds per minute for up to eight ten-minute observations during the 45 four-hour surveys. The number of scanning bouts from focal male and female seals was analyzed. Overall results suggest that females scan more frequently. The differences between scanning bouts were significant when comparing seals near the water. Females near the water scanned significantly more than males on surveys with below average disturbance levels and above average seal counts indicating that several factors may have an influence on female scanning behavior. (Regular Poster Session, Tuesday evening, Gym)

113 Variabilty in maternal transport among rhesus macaques during the first thirteen weeks

Jessica Ganas*, Nancy Megna & Dario Maestripieri

Emory University & Yerkes Primate Research Center (JGANAS@EMORY.EDU)

This study represents the first systematic investigation of variability in maternal transport in rhesus macaques, Macaca mulatta. Infant carrying preferences were investigated among 88 mother-infant pairs living in three captive social groups during the first thirteen weeks of infant life. Maternal transport was compared among groups and analyzed in relation to variables such as parity, age, rank, infant sex, matriline and maternal style. Generally, ventral carrying decreased and dorsal carrying increased over time. Mothers who physically abused their infants carried dorsally earlier and at a higher rate than non abusive mothers. Dorsal carrying also occurred more frequently among the oldest, lower ranking females. There was a significantly higher incidence of arm carrying in group three. Infant carrying style was not affected by the mother's coat condition. Rather, this study suggests that maternal transport is influenced by infant age, maternal style, parity, and dominance rank. Differences in maternal transport among groups or matrilines may result from observational learning. (Regular Poster Session, Tuesday evening, Gym)

115 Specialization in Thermoregulation in Bumble Bees

Kathryn E. Gardner* & Robin L. Foster

University of Puget Sound (kgardner@ups.edu)

Bumblebee colonies experience daily and seasonal ambient temperature fluctuations, but proper brood development requires a stable nest temperature. This study examined whether workers specialize in thermoregulation, expanding on previous evidence for division of labor in bumblebees. We videotaped three laboratory Bombus huntii colonies, and recorded incubation and fanning by individually marked bees. In one experiment colonies maintained a nest temperature close to 28 degrees C when exposed to ambient temperatures ranging from 10 to 35 degrees C. In cold conditions more bees incubated and for longer duration, and in hot conditions some bees fanned and others moved off the brood. A subset of bees incubated significantly more than did their nestmates, many of which never incubated, suggesting that some bees specialize in incubation. Small body size was the best predictor of high incubation rates, corroborating previous reports that body size regulates division of labor in bumblebees. In a second experiment we removed the most active incubators. Colonies compensated in two ways: of the remaining workers, some bees increased their incubation rates and other bees were recruited to the task. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

116 Stereotypic blue tits fail the same psychiatric task as stereotypic autists and schizophrenics

Joseph P. Garner* & Georgia J. Mason

University of California - Davis & University of Oxford - UK (jpgarner@ucdavis.edu)

Captive animals often develop strange, unvarying, repetitive and functionless behaviors called stereotypies – like the robotic route-tracing common in polar bears and big cats. We don’t really know why these behaviors are so common in captivity. A lot of people claim that these are coping, or boredom reliving behaviors, but there is no good evidence to support this view. You also see very similar behaviors in a number of human mental disorders, where they are associated with signs of dysfunction in a brain area called the basal ganglia. Psychiatrists have a number of simple tasks which can diagnose dysfunction in different brain areas. Accordingly, increasingly poor performance on the ‘gambling task’ (which measures basal ganglia dysfunction) correlates with increasing performance of stereotypy in autistic and schizophrenic patients. Luckily this task is easily modified for use with animals. We administered the task to blue tits which performed route tracing stereotypies, and the worse a bird did on the task, the more stereotypy it performed. This suggests that the stereotypies of the blue tits may involve similar brain mechanisms as stereotypies in human patients, which is a major breakthrough. Importantly, it suggests that the current veterinary approach to these behaviors (involving treatment with drugs like Prozac) may be inappropriate. (Applied Animal Behavior, Tuesday 11:30 AM - 11:45 AM, Sale)

118 Vocal communication in western lowland gorillas (Gorilla gorilla gorilla)

Stephanie Gibeault* & Suzanne E. MacDonald

York University (gibeault@yorku.ca)

The purpose of this study was to look at vocal communication in the western lowland gorilla, Gorilla gorilla gorilla. Over 100 hours were spent recording details about vocal communication in 25 western lowland gorillas, at four different zoos. For every vocalization that was heard, details such as the call type and the individual calling were recorded. This information was used to categorize the different vocalizations and to describe the possible function or meaning of each category. Over 15 different categories of vocalizations were identified. Results showed that certain vocalizations were used more frequently than others. Also, some calls were vocally responded to by the other animals. The calls that were responded to and that were used as responses were not in direct proportion to their frequency of use. This suggests that these vocal exchanges are not random but have a particular meaning to the animals. Also, the animals occasionally vocalized together, overlapping their calls, which may serve to coordinate the activities of group members when they can not see one another. Most calls were used by every animal, but a few were specific to individuals. This may be related to age and sex or to roles in the social system. (Evolution of Signals, Tuesday 11:30 AM - 11:45 AM, NMM1)

119 Seeing half the picture:behavioral and genetic data from sage grouse leks.

Robert Gibson*, K.E. Semple & R.K. Wayne

University of Nebraska & UCLA (rgibson2@unl.edu)

Current perceptions of sexual selection in lek-breeding birds are based largely on observations of mating behavior and have seldom been checked against genetic data. Retrospective analysis of data from past studies of sage grouse indicate that (i) although almost all observed matings are performed by males holding lek territories, only around half of adult males found on or near leks are territorial, and (ii) of radio-tagged females that visited intensely-observed leks at the time when they were expected to mate, less than half were observed mating. Examples from microsatellite DNA analyses of paternity confirm that females whose matings are not seen did not mate with territorial males at the lek they visited. Other observations exclude visits to other leks by these females, but not cryptic mating with non-territorial males at the lek periphery or away from a lek. These findings suggest that the lek mating system of sage grouse could be substantially different from that inferred from earlier studies. (Mate Choice 1, Sunday 11:30 AM - 11:45 AM, NMM2)

120 The pheromonal wedding ring hypothesis: female red-backed salamanders may possess a mechanism for avoiding polygynous males

Jennifer R. Gillette* & Robert G. Jaeger

University of Louisiana (prokyon33@hotmail.com)

Some animals benefit from avoiding potential partners that may be surreptitiously having a fling on the side. In such species, detecting and avoiding such partners may be very important. We wondered whether such detection and avoidance might occur in an animal that many people consider quite simple: the red-backed salamander, Plethodon cinereus. We tested whether male red-backed salamanders distinguish between females that have or have not recently cohabited with another male, and whether males discriminate between two single females, one of which bears secretions from another male. We also tested whether females discriminate between males that have or have not recently cohabited with another female, and whether females discriminate between two single males, one of which bears secretions from another female. We found that males were not affected by a female's recent associations (or lack thereof), but that females avoided males bearing odors from other females. We therefore suggest that female red-backed salamanders may discriminate against males that "smell" like other females. We term this the "pheromonal wedding ring hypothesis". In human terms, this might be reminiscent of women avoiding men at a singles bar that smell like perfume. Humans and salamanders may have some common ground, after all. (Mate Choice 4, Wednesday 10:15 AM - 10:30 AM, NMM2)

121 How do brown capuchins cope with short-term crowding?

May Lee Gong*, Michelle L. Berger, & Frans B. M. de Waal

Yerkes Regional Primate Research Center & Emory University (mgong@emory.edu)

High population density has traditionally been viewed as having a direct effect on aggression, although recent research on captive primates fails to support the hypothesis that crowding is invariably associated with an aggression increase. This study is the first to investigate the effects of crowding in a New World primate species. Two colonies of brown capuchins (Cebus apella) were observed under two conditions: a control condition and a short-term experimental condition in which the colonies were restricted to half the space of the control condition. Hourly rates of self-grooming, aggression, contact-sitting, grooming, and play were compared across both conditions in a within-individual design. Self-grooming was the only behavior that increased significantly under the crowded condition, indicating an increased anxiety level as also suggested in other studies. High-level aggression, contact-sitting, play, and social grooming decreased significantly with crowding, suggesting that capuchins avoid social contact with increased spatial confinement. Based on these results, capuchins appear to occupy an intermediate position between chimpanzees and macaques when coping with acute crowding. This position is reflective of similarities in complex social behaviors shared by capuchins and chimpanzees. Supported by NSF (IBN-9603923). (Social Behavior 1, Monday 4:30 PM - 4:45 PM, NMM2)

129 The costs of ant slavery: evidence of prudent social parasitism

James F. Hare* & Thomas M. Alloway

University of Manitoba & University of Toronto - Erindale (harejf@cc.Umanitoba.CA)

Slave-making ants raid the nests of other ant species and kidnap larvae and pupae which are reared as slaves. Enslaved workers collect food, defend the slave-maker's nest, and care for slave-maker eggs, larvae and pupae. While slave labor helps slave-makers reproduce, it would seem to be detrimental to the species that are enslaved. We quantified the impacts of two slave-making ants, Protomognathus americanus and Leptothorax duloticus, on populations of their slave species by establishing enclosures with and without a slave-maker colony. Leptothorax duloticus wiped out virtually all colonies of the slave species they had access to. Protomognathus americanus, somewhat surprisingly, had no detectable impact on colonies of the slave species. For slave-makers to have an ongoing source of slaves, they must somehow reduce their impact on populations of the species they enslave. Leptothorax duloticus seems to achieve this by moving into nests that it raids, thus constantly moving and exploiting greener pastures. Protomognathus americanus employs what we can think of as advanced strategies, stewarding its slave resource by capturing and rearing slave reproductives, allowing adults in raided colonies to escape, and not moving into raided nests. (Social Behavior 2, Tuesday 4:15 PM - 4:30 PM, NMM1)

130 A dynamic model of sperm allocation in group breeders: Theory and preliminary data

W. Ed Harris*

Purdue University (eharris@bilbo.bio.purdue.edu)

Male sperm are generally very small compared to female ova, although each ejaculate may contain enormous numbers of them. Assuming sperm supplies are not unlimited, sperm production may restrict reproductive success in males. In fact, studies have shown that males of many species become sperm-depleted and thus, males may be adapted to economize their sperm output per mating opportunity. When both sexes mate multiply, as is common in many species, another factor affecting male reproductive success might be the intensity of competition he faces for fertilizing ova of a given female. I modeled sperm allocation in males in this context. I considered competition intensity, sperm supply and female availability as factor affecting male sperm allocation. Males are predicted to be relatively conservative with sperm when competition is high or sperm reserves are low. When females are decreasing in availability through time during the breeding season, males are predicted to be relatively extravagant with sperm allocation. I present preliminary data in the context of these predictions using a group-breeding salamander, Ambystoma texanum, as a model system. (Mate Choice 1, Sunday 10:45 AM - 11:00 AM, NMM2)

131 Fly switching with branches by Asian elephants

Lynette A. Hart* & Benjamin L. Hart

Center for Animals in Society & University of California - Davis (lahart@ucdavis.edu)

The use of branches by captive Asian elephants to repel flies is common in India and Nepal. We report here systematic studies on captive elephants in India showing that they readily modify branches, shortening the branches and removing stems from the side, making them more suitable for switching. We report also opportunistic observations of wild elephants using branches as fly switches while foraging. Fly switching with branches, including modifying the branch, may be the most common type of tool use by Asian elephants. (Animal Learning & Cognition, Tuesday 10:45 AM - 11:00 AM, Sale)

132 Age and parental behavior in house sparrows

Margret I. Hatch*

University of Kentucky (mihatc0@pop.uky.edu)

In many animals, the number of young produced generally increases with parental age. One way to account for this increase is that older individuals are expending more time and energy caring for offspring because their age makes it unlikely that they will survive to breed again. The second is that older individuals are more efficient in caring for offspring due to experience or skills accumulated with age. To test these two mechanisms, I compared how often first year and older house sparrows (Passer domesticus) returned to the nest to feed nestlings. Older sparrows produced more young in two out of three years for females and one out of three years for males. There was no significant difference in the number of trips made to the nest by first year vs. older birds. However, the number of feeding trips is a poor measure of time and energy because individuals may be engaging in activities other than foraging for nestlings while away from the nest. To more closely examine parental behavior I observed parents' foraging behavior away from the nest in order to determine whether older individuals spend more or less time foraging for young. (Parental Care 1, Sunday 10:45 AM - 11:00 AM, NMM1)

133 The armpit effect in cowbirds: self-referent phenotype matching in a brood parasite

Mark E. Hauber*, Paul W. Sherman & Dora Paprika

Cornell University (meh20@cornell.edu)

When people meet, they attempt to recognize each other by comparing physical features like eye color and nose shape to mental images formed during previous social encounters. Other primates, and numerous other vertebrates and invertebrates, also recognize mates and relatives in ways similar to humans. Whereas most birds and mammals learn species-identity from their parents and siblings, brood parasitic birds are unlikely to do so. Since parasites are raised by parents of other than their own species, early social learning predictably yields inadequate or misleading information. Conceivably, juvenile parasites might inspect and memorize aspects of their own phenotype, such as body color or vocalizations, and later match features of encountered individuals to these templates. We tested for this "armpit effect" by manipulating feather colors of parasitic brown-headed cowbird chicks (Molothrus ater), and found that later, as fledglings, they preferred adults colored like themselves. (Recognition & Mate Choice, Tuesday 1:30 PM - 1:45 PM, NMM1)

134 Dispersal strategies of breeders in the polygynandrous acorn woodpecker

Joseph Haydock* & Walter D. Koenig

University of California & Hastings Natural History Reservation (haydock@socrates.berkeley.edu)

Acorn woodpeckers are enormously interesting cooperatively breeding birds that have been the subject of a long-term study at Hastings Natural History Reservation, located in central coastal California since 1975. Social groups of acorn woodpeckers range from pairs to groups with cobreeding males, joint-nesting females and non-reproductive helpers. All group members participate in defending the territory and rearing nestlings. Breeding status is obtained through highly competitive power struggles involving coalitions of siblings from neighboring groups. Our current work asks why some individuals that have won power struggles subsequently abandon the group. We found that established breeders leave positions due to (1) intrasexual competition for reproduction, (2) incest avoidance, and (3) low territory quality. (Dispersal Symposium, Sunday 2:00 PM - 2:15 PM, Sale)

136 The effects of age, sex, and morphology on patterns of dominance and aggression in House Sparrows

Wendy K. Hein*, David Westneat & Joseph P. Poston

University of Kentucky (wkhein0@pop.uky.edu)

When animals live in social groups, competition over shared limited resources is inevitable. Interactions among individuals can lead to complex dominance hierarchies. Factors such as age (juvenile or adult), sex (male or female), coloration, and body size may be closely associated with the outcomes of such interactions. We examined the relationships between these factors and the dominance and aggression behavior of wintering house sparrows (Passer domesticus). We observed feeding stations and documented which birds won or lost interactions and their aggression level towards the other bird. We analyzed the effects and interactions of age, sex, and morphological characteristics on both dominance rank and levels of aggression. Aggression level is also predicted to be higher between birds of similar dominance rank. We give particular attention to the size of black bib of the male house sparrow, which has been suggested by other researchers to act as a status signal during interactions. However, it seems unlikely that badge size would correlate with dominance or aggression in this case. (Dominance & Resource Defense, Tuesday 9:45 AM - 10:00 AM, NMM2)

138 Parental care and sexual selection in Madagascan poison frogs

Heather E. Heying*

University of Michigan (hheying@biology.lsa.umich.edu)

Mantella laevigata, a species of poison frog, was investigated in the first field study of frog behaviour in Madagascar. These are small, terrestrial, diurnal, brightly colored frogs with skin toxins identical to those of the New World dart-poison frogs. Males are territorial, defending water-filled wells such as tree holes, which are used for oviposition. Extended fights between males are frequent--215 fights were observed in 925 hours of observation--and often interrupt courtships between males and females. Courtships follow elaborate, highly stereotyped sequences in which the male rubs his chin on the female's back repeatedly, while calling softly, before leading her to possible oviposition sites. Successful courtships usually result in a single egg being laid; this is the lowest known (and lowest possible) clutch size in amphibians. Mothers sometimes return to water-filled wells to feed their tadpoles unfertilized eggs, an extremely rare form of parental care in amphibians. Tadpoles also eat fertilized eggs, so females choosing a mating site discriminate against wells containing potentially cannibalistic tadpoles. Males also choose between possible oviposition sites, discriminating against wells containing predatory crane-fly larvae (the first known observations of crane-flies eating frog eggs). In addition, males discriminate against wells containing individuals of other species of frogs, even when they have preferred those wells when they were empty. Much of the behavior described is context-dependent. In choice experiments, females were revealed to be choosy about the territory they mate in, but not discriminate between males on the basis of their call quality or call duration. This runs counter to much amphibian sexual selection research, which has revealed that females usually choose males based on dominant frequency or components of the male's call. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

139 Calling song transect of two field cricket species: What tale does geographic variation tell?

Laura A. Higgins*

University of Texas - Austin (lhiggins@mail.utexas.edu)

My research examines how songs of crickets change over the range of a species. Male crickets call; female crickets choose who to mate with based in part on the song a male sings. Females don't have to worry about choosing the correct species when there is only one present. However, when two different species are present together, there is the opportunity for interspecies mating, which produces hybrids. This could change the geographical pattern of song. I am looking for this kind of species interaction by comparing songs in populations where just one species occurs (isolation) to populations where species co-occur (overlap). Three possibilities exist. (1) Each species is unaffected by the other in areas of overlap; there is no intermating and no change in songs. (2) The two species intermate and successfully hybridize, and songs become more similar in overlap due to hybridization. (3) The two species intermate but hybrids do poorly which causes females to choose songs that reduced intermating, and songs become more different in areas of overlap compared to isolation. The two species I study, Gryllus rubens and Texas G. integer, are the two most abundant field crickets in the Southeastern U.S. (Evolution of Signals, Tuesday 11:45 AM - 12:00 PM, NMM1)

140 Call convergence within groups of female budgerigars (Melopsittacus undulatus)

Arla G. Hile* & Georg F. Striedter

University of California - Irvine (ahile@uci.edu)

The budgerigar or parakeet (Melopsittacus undulatus), a popular pet bird, is also a promising model species for the study of adult vocal learning. Several studies shown that adult male budgerigars learn contact calls (a common budgerigar vocalization) rapidly. Vocal learning has not yet been investigated in female budgerigars. Since one likely function of the contact call is to denote group affiliation, we tested the hypothesis that female budgerigars, when placed into groups, would develop a shared contact call. We recorded the call repertoires of eight adult female budgerigars that were unfamiliar with one another, then placed them into two groups. Within 4 - 7 weeks females in both groups converged on a common call type. This rate of convergence is slower than that observed in prior experiments limited to male birds, and much slower than vocal imitation by male budgerigars paired with females. Therefore, while this study documents vocal learning in adult female budgerigars, it also suggests that female budgerigars learn new vocalizations more slowly than males do. The results of this study open up opportunities to study sex differences in specific brain regions, and also suggests that vocal learning may play a role in mating strategies. (Learning of Social Signals, Sunday 4:45 PM - 5:00 PM, NMM1)

142 Sexual selection in golden pheasants: Female mate choice, male-male competition, and offspring quality

Jennifer Hill*

University of New Mexico (jahill@unm.edu)

What they want is what they get. We studied how female mate choice leads to the evolution of colorful plumage displays. We gave females of various species of finches a choice of males that either looked like males of that species normally do or that had color displays greater than those normally seen in that species. We found that females preferred as mates males that looked normal. This result is important in helping us understand how bright color displays come to be because it shows that male appearance and female color preference change in unison not independently as predicted by some biologists. (Sexual Selection, Sunday 4:45 PM - 5:00 PM, NMM2)

143 The effects of environmental enrichment on mate choice in prairie voles Kelli D. Hinze-Bemis*, Andrea Bixler & Zuleyma Tang-Martinez University of Missouri - St. Louis (khb@umsl.edu)

Studies of non-mammalian polygynous species have suggested that resource abundance is important in mate selection. Such studies on monogamous animals are rare. We tested whether resource abundance is important in the prairie vole, Microtus ochrogaster, a highly social, monogamous rodent. We offered females a choice between two males, unrelated and unfamiliar to her, one of whom was housed in a compartment with various forms of enrichment (apples, extra food and bedding, and a nest box.) The other male's compartment contained only the standard amount of food and bedding. Observations were recorded for one hour, including visiting time with each male, huddling, allo-grooming and mating. We hypothesized that the subjects would mate significantly more often with the targets in the enriched environment. Preliminary results support this hypothesis. This suggests that resource abundance may be important in mate choice selection. These findings could have profound effects on the use of environmental enrichment in captive breeding. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

144 The behavior of a social group of gorillas following the death of the silverback male

Michael P. Hoff* & Terry L. Maple

Dalton State College & Zoo Atlanta (mhoff@em.daltonstate.edu)

This study examined the response of a group of 10 gorillas to the death of the silverback male who led the group over a number of years. In the wild, gorilla groups are typically composed of a silverback male, several adult females, subadult males and females and immature gorillas. The group is led and protected by the silverback male. In captivity, zoos attempt to recreate the wild condition as much as possible. However, it is relatively rare to find groups of more than several animals. Zoo Atlanta had an 11-member group composed of the silverback male, Willie B., 4 adult females and 6 immatures.The group had been studied for years, focusing on infant development, mother-infant interactions and general social behaviors. This study examined the behavior of group members prior versus following Willie B.’s death in Feb., 2000. We found an increase in aggressive Displaysamong the remaining group members, as well as a variety of other changes in social and individual patterns of behavior, including leaving and approaching one another, spatial relationships, eating and self-grooming. The role of the adult male in controlling and leading the group is discussed in this paper. (Social Behavior 2, Tuesday 3:45 PM - 4:00 PM, NMM1)

145 Contingent behavior in a cichlid fish: When the cat is away the mice will play.

Hans A. Hofmann*, Lyen Huang & Russell D. Fernald

Stanford University (hans@psych.stanford.edu)

Understanding social behavior depends ultimately on observing many animals simultaneously. However, animals are often studied in isolation or in reduced laboratory settings where only two animals interact in a staged context. Such paradigms make it difficult to know how the presence of conspecifics influences behavior and physiology of individuals. We have begun experiments directed at discovering how individual behavior both regulates and is regulated by the social scene. The complex social behavior of the African cichlid Haplochromis burtoni lends itself to this work for several reasons. In this species, brightly colored males defend territories, chase nonterritorial animals (NTs), and court females, in contrast to cryptically colored NTs which are not reproductive and school together with females. Changing social status causes well-documented changes in reproductive physiology and growth.

Using video analysis of a H. burtoni community, we found that some subordinate males adjust their behavior contingent upon the actions of the dominant male. Specifically, these "intermediate" fish perform significantly more aggressive Displayswhile the dominant male is in his shelter or soliciting and courting potential mates than when the dominant male is not so occupied. And even when the dominant fish is attending to the subordinates, their actions do not overlap with his. Animals who switch status also change this contingent behavior showing that it is dependent on social status rather than on individuals. Future experiments will assess the physiological consequences of such contingent behavior. Supported by NIH NS 34950 to RDF. (Dominance & Resource Defense, Tuesday 9:30 AM - 9:45 AM, NMM2)

146 The avoidance of chemical alarm cues released from the autotomized tails of ravine salamanders

Jeffrey A. Hucko* & Paul V. Cupp, Jr.

University of Louisiana at Lafayette (jhucko@rocketmail.com)

The ability of animals to detect and avoid areas containing chemical alarm cues from conspecifics is well documented in aquatic species. The ability to detect chemical alarm cues in terrestrial organisms, until recently has been untested. In this study, I tested the ability of the ravine salamander Plethodon richmondi, to detect and avoid areas containing chemicals released from the autotomized tails of conspecifics and the sympatric zig zag salamander, P. dorsalis. I also collected data to determine if any avoidance response could be attributed to the size or sex of the animal. The results of this study suggest that P. richmondi will avoid substrates containing odors released from the autotomized tails of conspecifics, but not P. dorsalis, and this response occurs independent of the size and/or sex of the animal. (Anti-predator Behavior, Tuesday 5:15 PM - 5:30 PM, NMM2)

148 Seasonal variation in neighbor / stranger recognition in Carolina wrens

Jeremy Daniel Hyman*

University of North Carolina (jhyman@email.unc.edu)

Recognition of territorial neighbors could benefit a territorial animal by allowing it to avoid territorial contests with neighbors with whom it has previously interacted. Reduced aggression toward established neighbors, known as the dear enemy effect, could result in mutual benefit for neighbors by allowing them to reduce the time and energy spent defending shared territorial boundaries. However, the dear enemy effect might disappear if neighbors and strangers represent similar threats to territory owners. Using playback experiments, I examined neighbors/stranger discrimination (NSD) in Carolina wrens, Thryothorus ludovicianus, in two different social environments: In Spring when territories have been established for several months, and in Fall when first year birds settle new territories, often placing them alongside or even in-between the territories of established older birds. An influx of new birds and new territories might cause formerly established territorial boundaries to become unsettled and increase aggression among established residents. I found that Carolina wrens show NSD in spring, but do not show NSD in fall. This study is one of the first to document a seasonal change in NSD in response to changing social environments. (W.C. Allee Competition, Monday 11:45 AM - 12:00 PM, Sale)

151 Multiple ornaments in female Northern Cardinals (Cardinalis cardinalis) and correlates of individual quality

Jodie Jawor* & Randall Breitwisch

University of Dayton (jawor@neelix.udayton.edu)

Female ornamentation and its correlation with measures of individual quality have only recently been investigated in birds. Previous research on this population of Northern Cardinals (Cardinalis cardinalis) found that more ornamented females [brighter red underwing coverts] provisioned nestlings at higher rates than less ornamented females (Linville et al. 1998 Anim. Behav. 55:119). This study tests for correlations between measures of individual quality in female cardinals and a suite of five visual ornaments. A pilot study in 1999 indicated that underwing covert brightness was associated with a more conspicuous black face mask which, in turn, was correlated with two measures of physical condition. Data will be reported from the 2000 breeding season. (Regular Poster Session, Tuesday evening, Gym)

152 Evidence for signature characteristics in bugles of elk in Rocky Mountain National Park

Jennifer A. Johnson* & Jennifer A. Clarke

University of Northern Colorado (Delphi875@aol.com)

Food neophobia is measured as a hesitancy to eat a new food and can be observed in most animals including humans. This behavior was investigated in a population of rhesus macaques that range freely on an island off the coast of South Carolina. It was hypothesized that food neophobia develops in primates after repeated experiences of illness caused by eating toxic novel foods present in the environment. If this hypothesis is correct then we would not expect to observe food neophobia in very young macaques or macaques born and raised in a restrictive captive environment. The author found that corral-housed monkeys did not exhibit food neophobia while island-living monkeys did. Island-living macaques as young as one-year old exhibited neophobic behavior. Though this last result does not support the illness hypothesis, observations need to be conducted on even younger infants. Pilot data show that aside from the presence or absence of food neophobia in six-month old macaques, social cues are available from infants' group members that could greatly influence their feeding behavior. These future results will add significantly to the current debate about whether primate infants rely on social or individual learning mechanisms when developing a species-typical diet. (Recognition & Mate Choice, Tuesday 1:45 PM - 2:00 PM, NMM1)

153 Sexual cannibalism and fecundity selection in fishing spiders, Dolomedes triton: evaluating a behavioral correlation explanation for female aggression at mating

J. Chad Johnson*

University of Kentucky (jcjohn4@pop.uky.edu)

This study attempts to determine whether female fishing spiders eat courting males to gain nutrients, or whether they have such high levels of overall aggression that they attack males as prey items before recognizing them as potential mates. The latter hypothesis is part of a growing field in animal behavior which notes that organisms, including humans, often Display behavioral syndromes which result in positive correlations between behaviors in different contexts (e.g. aggression at feeding and aggression at mating). Results indicate that females may, in fact, be limited by their own aggressive tendencies. (Mate Choice 2, Sunday 3:15 PM - 3:30 PM, NMM2)

155 Early maternal recognition of offspring vocalizations in Rhesus Macaques (Macaca mulatta)

Tanja Jovanovic*, Nancy Megna & Dario Maestripieri

Emory University & University of Chicago (tjovano@emory.edu)

It is well known that monkeys can recognize their infants after a few months of age. However, little is known about how this recognition develops over time. Are there some biological markers that allow mothers to recognize the cries of their own babies immediately after birth? Or do mothers need to learn the specific characteristics of their infants’ cries? In this study we tested fifteen rhesus macaque mothers with their infants by playing the recorded calls of their own and strange infants from a cassette player. The infants ranged in age from one to 28 days of age. We found that mothers of infants older than one week responded more vigorously to the cries of their infants than to those of the strange infants. However, mothers whose infants were less than one week old did not respond more to the cries of their own infants. This study is the only one to look at maternal recognition of calls using very young macaque infants. It suggests that mothers need to hear their infants for a week before learning to recognize their calls; monkey mothers do not seem to inherently distinguish the cries of their own newborns from those of other infants. (Parental Care 2, Sunday 1:45 PM - 2:00 PM, NMM1)

157 The effect of female coloration on mate choice by male Convict Cichlids

Teresa C. Justice* & Michael Bailey

Chowan College - NC (justit@chowan.edu)

Previous studies have investigated the effects of female size and ventral coloration on mate choice in male convict cichlids. The purpose of the present investigation was to examine the effect of overall darkness of females on mate selection. Convict cichlids are gray with black vertical stripes. The gray area between the stripes can be light or dark. When the gray area is dark, the overall appearance of the fish is dark. Twenty males were presented two females, one female appeared light and the other female appeared dark. The females were placed into clear containers and placed on opposite ends of a tank housing a male. Blinds were used to prevent the females from seeing one another. The fish were housed together for approximately 24 hours before observation. An observer recorded the amount of time the male spent with each female for a thirty-minute period. The males spent an average of 12.29 minutes with the dark colored females and an average of 13.21 minutes with the light colored females. The amount of time the males spent with the dark females did not differ from the amount of time the males spent with the light females (t=0.23, p=0.823). (Regular Poster Session, Tuesday evening, Gym)

161 Training Captive-born Animals for Reintroduction to the Wild

Devra G. Kleiman* & Benjamin Beck

Smithsonian Institute & National Zoo (dkleiman@nzp.si.edu)

We will review reintroduction programs for endangered species of birds and mammals involving pre- and post- release training in foraging and feeding, locomotor, orientation and navigation, anti-predator and species-specific social skills. We will discuss the best age groups for training and release; what type of training has been accomplished and in which behaviors; how the training has been conducted; and how much.and how long training has continued. We will discuss the impact of training on survivorship after release as well as observed changes in behavior not accompanied by increased survivorship. We will present data on the lack of effect of training on golden lion tamarin survival after release. (Applied Animal Behavior Symposium, Tuesday 4:45 PM - 5:15 PM, Sale)

164 The Influence of Mating Status and Age on Sexual Cannibalism in the Fishing Spider, Dolomedes triton

Nancy A. Kreiter*, Kim Getz, & Julee Johns

College of Notre Dame of Maryland (nkreiter@ndm.edu)

Cannibalism of males by females in the context of mating is known as sexual cannibalism. Female fishing spiders cannibalize males both in the field and laboratory. Our study looked at how previous mating activity and female age influence the probability of cannibalism in the fishing spider Dolomedes triton. We tested whether cannibalism of males by females decreases as females grow older (and opportunities to mate become less likely) and whether previous mating make is more likely that a female cannibalizes. We introduced female spiders of different ages and mating histories to males in the laboratory. Males courted virgin and mated adults, but not juveniles. Copulation occurred in 50% of trials with virgin females; only 1 mated female (4%) copulated a second time. Fewer trials with juveniles (13%) and virgin females (13%) resulted in cannibalism than trials with mated females (43%). Virgin females older than 14 days post-molt never cannibalized, but mated females continued to cannibalize at all ages. Our results indicate that female D. triton do not cannibalize indiscriminately. Reproductive status, previous sperm acquisition, and fertilization opportunities may all be important factors in determining whether female fishing spiders cannibalize their male suitors. (Mating & Reproductive Success, Monday 5:30 PM - 5:45 PM, NMM1)

165 The effects of food restriction on hormone levels and mate preferences in Mus musculus.

Jill H. Kruper*

Murray State University (jill.kruper@murraystate.edu)

Odor cues are known to play a significant role in conveying information about individual identification, territorial boundaries, and reproductive condition in mammalian species. I tested the effects of odor cues on mate preferences in wild house mice (Mus musculus). Specifically, I tested whether food restriction of males prior to and after birth altered the attractiveness of their odors to females. In addition, I tested whether food restriction of males altered their levels of testosterone and/or prolactin. Control mice had significantly elevated levels of testosterone compared with males food restricted after birth. The attractiveness of male odors to females was positively correlated with male testosterone level. Despite the correlation between testosterone level and attractiveness of male odors, there was no significant relationship between male testosterone or prolactin level and female nesting preferences. These data indicate that testosterone level influences the attractiveness of male odors to females, but attractiveness of male odors is not indicative of female nesting preferences. (Regular Poster Session, Tuesday evening, Gym)

169 Variation in egg appearance and rejection of dissimilar eggs in a weaverbird

David C. Lahti* & April R. Lahti

University of Michigan (lahtid@umich.edu)

Most birds lay eggs of consistent appearance; but in some birds, eggs of different individuals look very different from each other. The African village weaverbird, for example, lays eggs of a wide variety of colors and spotting patterns among individuals. Weaverbirds with distinctive eggs might be able to tell them apart from those of other birds, especially cuckoos which are known to lay their eggs in weaverbird nests, and whose young kill all of the weaverbird young in the nest. We tested this hypothesis by playing the cuckoo and placing eggs of various colors and spotting patterns into 143 weaverbird nests in The Gambia, Africa. Our results clearly indicate that weaverbirds do reject foreign eggs, unless the foreign ones are very similar in color and spotting to their own, in which case the birds are fooled into accepting them. We also found that weaverbirds memorize the appearance of their own eggs, as they are able to reject different-looking foreign eggs even if none of their own eggs are in the nest for comparison. This ability would be useful, or adaptive, when birds returning to their nests are in danger of finding eggs that are not theirs. (Regular Poster Session, Tuesday evening, Gym)

170 Landmarks and territory establishment in a Cichlid Fish

Justin R. LaManna* & Perri K. Eason

University of Louisville (jlamanna@louisville.edu)

Many species use landmarks to define territorial boundaries. This laboratory study examined the use of territorial landmarks in a cichlid fish, the blockhead (Steatocranus casuarius). First, blockheads were paired in 10-gallon aquaria. Then two established pairs were introduced into a 29-gallon aquarium but were separated from each other by two opaque dividers placed 5cm on either side of the tank's center. After acclimation we removed the dividers and recorded the blockheads' behavior as the two pairs attempted to establish territorial boundaries. In experimental trials, we placed a line of large, flat rocks across the center of the tank; there was no landmark in control trials. A total of 15 trials were run. Pairs in experimental trials used the line of rocks as their territorial border. These fish had significantly fewer aggressive interactions than did fish with no landmarks, and their interactions were significantly shorter and of lower intensity. Thus, the presence of landmarks at territorial borders reduced the costs of territorial defense; this reduction in costs is a selective advantage that could evolutionarily favor the use of landmarks.

(Dominance & Resource Defense, Tuesday 10:30 AM - 10:45 AM, NMM2)

171 Who does what to whom?: Affiliative behavior in common marmoset nuclear families

Theodore Lawler*, Kosunique T. Jenkins, John D. Newman & R. Lucille Roberts

Laboratory of Comparative Ethology/ NICHD (LawlerT@mail.nih.gov)

Affiliative interactions are reported to occur frequently among members of common marmoset (Callithrix j. jacchus) families. Few studies have examined affiliation among family members other than the breeding pair. The present study examined interactions within eight common marmoset families and quantified the types of affiliation shown. Family groups were observed weekly in thirty-minute ad libitum focal sessions. Frequency and duration of lateral contact, infant carrying and frequency of allogrooming were observed. Initiators and recipients of contact were recorded. Mothers and fathers showed the highest frequency of lateral contact and allogrooming. Fathers were most often initiators of contact. Frequency of lateral contact initiated by both parents towards infants (_ 5 months old) was similar. Duration of lateral contact was longest during mother-infant contact exclusive of infant-carrying. Fathers groomed and carried infants significantly more than did mothers and subadults. Infants initiated longer and more frequent lateral contact with fathers than with other group members. Subadults participated in affiliative interactions significantly less often than parents and infants. The results of this study indicate that marmoset parents focus affiliative behavior toward their infants and mates, reducing their efforts toward subadults. These results provide valuable descriptive data regarding affiliative behavior of primate nuclear families.

(Regular Poster Session, Tuesday evening, Gym)

172 Avoiding versus confronting the predator: endurance capacity influences escape tactics in Anolis lizards

Manuel Leal*

Washington University in St. Louis (mleal@biology.wustl.edu)

Current theory on the evolution of pursuit deterrent signals predicts that differences between sympatric species in the use of this escape tactic is correlated with differences in prey’s ability to escape an attack. I tested this prediction by comparing the antipredator responses given by two sympatric species of lizards, Anolis cristatellus and A. gundlachi, during staged predatory encounters under natural conditions. Results demonstrated that A. cristatellus and A. gundlachi employ different escape tactics. Anolis cristatellus employed pushups in accordance with the pursuit deterrent signals hypothesis, whereas A. gundlachi exhibited flight. Furthermore, A. cristatellus has a significantly higher physiological capacity than A. gundlachi, measured as endurance capacity. Because endurance capacity can be a critical aspect limiting the ability of anoles to escape a predatory attack, the results support the prediction that interspecific differences in physiological capacity can lead to interspecific differences in the use of pursuit deterrent signals.

(Anti-predator Behavior, Tuesday 4:00 PM - 4:15 PM, NMM2)

175 Geographic variation in the songs of Ochre-bellied Flycatchers

Daniel W. Leger*

University of Nebraska (dleger1@unl.edu)

Several species of birds differ more in their song than in their plumage or other anatomical features. In this paper I present evidence that a small bird, the Ochre-bellied Flycatcher of Central and South American rainforests, may in fact be at least three species. Although these birds look much the same throughout their large range, the songs differ significantly. Further, the differences in song occur across boundaries that would impede the movement of this species, such as mountain ranges. Careful analyses of song may reveal more bird species than we currently recognize. (Evolution of Signals, Tuesday 11:15 AM - 11:30 AM, NMM1)

177 Meadow voles respond preferentially to the hormonal condition of a scent donor rather than its position in an over-mark

Stuart Leonard*

University of Memphis (sleonard@memphis.edu)

Scent over-marking occurs when an animal places its scent mark directly on top of another individual's scent mark. Typically, a preference for the mark of the top-scent donor is shown over that of the bottom-scent donor. Situations, however, may arise in which the top-scent donor is a lower quality individual relative to the bottom-scent donor. How should animals respond to such an over-mark? Do they prefer the odor of the top-scent donor, independent of its quality, or do they prefer the higher quality scent donor even if it may be the bottom-scent donor? Using gonadal hormone status as an indicator of donor scent quality, we tested the hypothesis that adult meadow voles preferentially respond to a higher quality donor (gonadectomized and appropriate sex steroid replacement) over a lower quality donor (gondadectomized and no sex steroid replacement), independent of the position of the scent marks in an over-mark. Overall, our findings suggest that male and female meadow voles differ in how they respond to an over-mark of two scent donors that differ in quality. Males appear to use the quality of the female scent donor, not its position in an over-mark. Females, on the other hand, appear to use position of the male scent donor, not its quality. (Mating Behavior, Monday 10:45 AM - 11:00 AM, NMM1)

180 Body size affects the ability of male spiders to travel to female webs

Christopher Linn* & Terry E. Christenson

Tulane University (clinn@mailhost.tcs.tulane.edu)

The golden orb-weaving spider, Nephila clavipes, has been intensively studied in terms of courtship and copulation, as have many spider species. It is accepted that larger males have an advantage in struggles to mate with females. There is considerable variability in male size however, and all males are many times smaller than females. Proposed explanations for sexual size dimorphism have included female fecundity selection, selection for early maturation by males, and selective cannibalism by females. The movement of males to find females is relatively unstudied with regard to size. I investigated the role of male size in movement to find females. Field observations as well as capture and release experiments demonstrated that smaller males travel further distances in shorter periods of time. Furthermore, smaller males are more likely to find their way to female webs than larger males. During instances when more than one male reached a single female, larger males nearly always positioned closest to the female, corroborating previous research. Cannibalism by females was rarely observed and did not appear to be related to male size. Differential male size therefore appears to be a critical aspect of the reproductive success of males required to travel vast distances to reach females. (Mating & Reproductive Success, Monday 5:00 PM - 5:15 PM, NMM1)

181 Social influence on song use by chipping sparrows: evidence from removal experiments

Wan-chun Liu*

University of Massachusetts (wliu@bio.umass.edu)

How do social factors influence the singing behaviors of songbirds? To explore this question, I conducted a series of removal experiments from nine territorial clusters of chipping sparrows Spizella passerina and observed how the presence or absence of neighboring males or changes in pairing status affected the focal male's singing behaviors at different times of the day. I found that, after removing a territorial male's neighbor (n=9), the new solitary male, whether paired or unpaired, soon reduced (n=6) or stopped (n=3) his dawn chorus, yet did not change his singing pattern during the daytime. Following the release of a male's neighbor, all of these focal males immediately resumed their dawn chorus. On the other hand, after removing a male's mate, these experimentally-widowed males (n=3) did not seem to alter their singing pattern at dawn, yet did resume their daytime singing and sing like unpaired males. These results, which are consistent with my previous field observations, suggest that dawn song and daytime song of chipping sparrows represent different signal values. Dawn song appears to function primarily for interactions between neighboring birds, whereas the daytime song appears to function primarily as a long distance territorial advertisement to females. (W.C. Allee Competition, Monday 1:45 PM - 2:00 PM, Sale)

182 Natal recruitment in a population of nine-banded armadillos

William J. Loughry* & Colleen McDonough

Valdosta State University (jloughry@valdosta.edu)

Nine-banded armadillos give birth to litters of genetically identical quadruplets. Littermates remain together for some portion of their first summer above ground, but what happens to them subsequently? We caught and marked 146 juvenile nine-banded armadillos at a study site in northern Florida during 7 field seasons between 1992 and 1999. Of these, 22 of 69 males and 17 of 77 females were recaptured in a subsequent field season. In 5 cases, multiple members of male litters were recruited (3 groups of 2 siblings, 2 groups of 3 siblings), but we recorded only 1 instance of female littermate recruitment (1 group of 2). Males and females moved equally far from where they were caught as juveniles to where they were found as adults. Genetically identical siblings were significantly more widely dispersed as adults than they were as juveniles, thus limiting opportunities for interaction among clonemates. The attributes of juveniles recruited into the population did not differ from those not recruited, suggesting that natal philopatry may be relatively random in this population. (Regular Poster Session, Tuesday evening, Gym)

184 Social mitigation of neophobia in Eastern Kingbirds (Tyrannus tyrannus)

Sarah E. Mabey*

University of Sourthern Mississippi (sarah.mabey@usm.edu)

Migratory songbirds encounter a variety of unfamiliar resources during the course of migration. I investigated the question of whether songbirds in flocks might use the behavior of flock-mates to determine the safety and profitability of exploiting these unfamiliar resources. I tested the responses 16 naive, adult Eastern Kingbirds to novel feeding opportunities while in the presence of another naive kingbird and in the presence of an "experienced" kingbird, for whom the feeding opportunity was familiar. The results of these tests indicate that naive kingbirds are generally reluctant to approach unfamiliar objects (i.e., they are "neophobic"). Their neophobia was alleviated by the presence of an experienced neighbor but not by the presence of another naive bird. These results suggest that inexperienced Eastern Kingbirds that join flocks during migration can learn from other kingbirds and consequently benefit by being able to exploit a wider range of resources. (Social Behavior 1, Monday 3:00 PM - 3:15 PM, NMM2)

189 Behavior Matters: developing an animal behavior curriculum for middle and high school students

Susan W. Margulis

Brookfield Zoo & Northwestern University (s-margulis@nwu.edu)

Animal behavior, if it is taught at all at the high school level, is relegated to a few days, late in the school year. Here, I describe a 4-week animal behavior curriculum, "Behavior Matters," that serves as an introduction to the scientific method, and introduces students to animal behavior and its relevance to solving real-world conservation problems. We capitalize on the natural fascination children have for animals and leverage this to engage students. Developed collaboratively by the Center for Learning Technologies in Urban Schools and Brookfield Zoo, the unit includes a series of lead-in activities, a videotape, and a software program. The unit concludes with a field trip to Brookfield Zoo, where students collect and interpret real data. Here, I describe results of the initial use of the curriculum in middle and high schools during the 1999-2000 school year, and the collaborative process that enabled us to develop a curriculum that is teacher-friendly, scientifically accurate, and fun for students.

188 Breaching Behavior In Barred Sand Bass During the Spawning Season

Melanie Moore* and Susan W. Margulis

Brookfield Zoo, Northwestern University (s-margulis@nwu.edu)

Breaching occurs when bass swim with their dorsal fins protruding from the surface of the water. The barred sand bass is a major component of the nearshore marine environment in southern California. They are one of the most sought after game fishes off the California Coast. During the summer they form large spawning aggregations in shallow areas where they relese their eggs. Complete knowledge of the behavior of the barred sand bass is necessary for the proper management of this increasingly popular resource. Breaching, a previously unknown behavior for this species, was observed seasonally in a captive population at the Brookfield Zoo in Illinois. This study focuses on the possible relevance of breaching to spawning behavior. The daily activities and interactions of each individual were obtained in fifteen minute intervals to gain more insight to the cause of this behavior. The collected observations revealed that the larger basses paired and breached more frequently than the smaller basses. Males and females were sited most frequently in proximity to members of the opposite sex. Other aspects of this behavior will be presented.

193 Arginine vasotocin changes calling behavior and calling-site acquisition in male grey treefrogs

Patricia A. Martin, Katharine Semsar, Kurt Klomberg & Catherine A. Marler*

University of Wisconsin & N. Carolina State University (camarler@facstaff.wisc.edu)

Arginine vasotocin (AVT) is a neuropeptide hormone that influences acoustic communication in a number of taxa. In contrast to other studies suggesting that AVT only influences probability of calling in anurans, we demonstrate that AVT can have more complex effects on calling behavior. In the gray treefrog, Hyla versicolor, peripheral injections of AVT increase an intruder male's ability to acquire a calling site under field conditions, without using aggressive calls or physical aggression. This ability to acquire calling sites may be influenced by advertisement call changes induced by AVT. Males injected with AVT give longer calls with more pulses. Other researchers have demonstrated that these call traits are attractive to females. Preliminary data indicate that intracerebroventricular injections of AVT given under semi-natural field conditions induce the same behavioral changes as peripheral injections. Overall, these studies suggest AVT significantly influences acoustic communication by acting directly on the central nervous system to induce behavioral changes not only in the injected individuals, but also in individuals in their social environment. (Mating Behavior, Monday 11:15 AM - 11:30 AM, NMM1)

195 Evolution of social monogamy in snapping shrimp (Decapoda: Alpheidae)

Lauren Mathews*

University of Louisiana (lmm4706@louisiana.edu)

One of the most mysterious problems facing behavioral ecologists has been the relatively common occurrence of monogamy. Evolutionary theory predicts that monogamy should be rare, because males should be under strong sexual selection to gain as many mates as possible, yet many species have social systems in which males and females form pairs, potentially with some level of mating exclusivity. Social monogamy is widespread in snapping shrimp of the genus Alpheus. Because male snapping shrimp do not participate in care of the young, monogamy may have evolved either as a result of selection on males to "guard" individual females from other males for extended periods, or as a result of advantages garnered by one or both sexes through cooperation in territory defense. My research has provided no support for the mate-guarding hypothesis, but in laboratory experiments, females did enjoy a reduced risk of eviction from the territory (by an intruding shrimp) as a result of shared territory defense with a male partner. Interestingly, males did not enjoy the same benefit as females through joint territory defense. Instead, males based decisions about defense on the "value" of their mates: males with "valuable," nearly sexually receptive females were less likely to leave the territory and their mates than were males with less "valuable" females. (W.C. Allee Competition, Monday 2:00 PM - 2:15 PM, Sale)

196 Predation risk, foraging and group membership in barnacles

Robert Mauck* & Kelly C. Harkless

Ohio State University (rmauck@osu.edu)

Animals living in groups are thought to gain fitness through decreased predation risk, while often paying a cost in terms of increased competition in foraging. Thus, the balance struck between predator avoidance and foraging should be affected by group membership. For animals that avoid predation by hiding, such as the northern rock barnacle (Semibalanus balanoides), that balance is particularly important since predator avoidance excludes foraging altogether. We tested the hypothesis that barnacles living in groups should spend less time hiding when faced with a perceived threat than should solitary barnacles. We presented group-living and solitary barnacles with a simulated threat and measured hiding time with the prediction that barnacles in groups would return to foraging more quickly than would solitary barnacles. We then manipulated barnacle group size using an A-B-A design in which barnacles were tested in one of two sequences, solitary-group-solitary, or group-solitary-group. We found that group membership had a significant effect on the barnacle foraging behavior in that individuals emerged from hiding sooner when tested in a group than when tested alone. We conclude that group membership strongly affects foraging decisions by this simple, refuge-using animal. (Anti-predator Behavior, Tuesday 3:00 PM - 3:15 PM, NMM2)

198 Effects of injured-prey cue on behavior during predator-prey interactions

Thomas M. McCarthy* & Brad Dickey

University of Kentucky (tmmcca0@pop.uky.edu)

Chemical signals are an important influence on interactions between predators and prey. From a prey’s perspective, for example, why do people fear swimming when there is blood in the water? From a predator’s perspective, have you ever felt hungry only after you smelled food cooking? Studies have shown that injured prey can release chemicals that warn others of potential danger. However, predators that also detect these chemicals might begin hunting. Therefore, there should be a race of responses between the predators (trying to catch prey) and the prey (trying to avoid predators). We examined how predators and prey respond to chemical cues by observing interactions between aquatic snails (prey) and two species of crayfish (predators). After detecting the cues, snails avoided predators by moving to the waterline, floating, or crawling out of the water. Crayfish responded to the cues differently: one species significantly increased their activity rates after exposure to the chemicals (low activity to high activity), but the other species always had high activity rates. These differences suggest the crayfish have alternative foraging strategies. Crayfish of both species consumed snails faster when exposed to the cues, but differences between treatments were not significant, perhaps as a result of the snails’ avoidance responses. (Anti-predator Behavior, Tuesday 3:15 PM - 3:30 PM, NMM2)

199 The Social Development of Maternally Maltreated Rhesus Macaque Infants

Kai McCormack*, Nancy L. Megna & Dario Maestripieri

University of Georgia, Yerkes Regional Primate Center & University of Chicago (kaim@arches.uga.edu)

This study examined the development of social behaviors during the first three months of life in maternally maltreated and non-maltreated rhesus macaques, Macaca mulatta. Based on attachment theory and previous primate studies, it was predicted that maltreated infants would be less likely to leave their mothers, explore the social environment, and play with their peers than non-maltreated infants. Four abusive and five non-abusive female rhesus monkeys were observed with their infants during the first 12 weeks of the infant's life in a captive group at the Yerkes Field Station. Results show that maltreated infants engaged in play with others at a later age, and less frequently than did the controls. Maltreated infants were rejected more by their mothers and experienced an increase in rejection over the twelve weeks compared to the controls. Maltreated infants were also more likely to be kidnapped and harassed by adult females during the first ten weeks. The findings of this study suggest that infant social development in rhesus macaques is affected by early maltreatment and are consistent with the results of previous studies of infant maltreatment in humans and other primates. (Regular Poster Session, Tuesday evening, Gym)

201 Forty years of solitude: Divergence between lines of D. melanogaster

Kenneth W. McDonald* & Christine R. B. Boake

University of Tennessee (lemur73@bellsouth.net)

The most common route to speciation is thought to involve the physical isolation of two populations, which allows genetic differences to accumulate. Recent mathematical models suggest that in small populations, sexual selection can be a potent force driving speciation. We report studies of a potential model system for such isolation, two lines of D. melanogaster that were selected in the mid 1950's, one for DDT resistance and the other as a susceptible control. The resistant line experienced repeated bottlenecks during its initiation. In the ensuing approximately 1500 generations, these lines have not been outbred. A decade after the original selection, the lines were found to differ in fertility, fecundity, and longevity. We have remeasured these life history traits and have also tested for behavioral isolation in all combinations between the two lines and Oregon-R, a wild-type laboratory stock. Life history characters have changed since 1966 but in complex ways not predicted by the earlier authors. Furthermore, behavioral isolation may be developing between Oregon-R and at least one of the lines. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

202 Variation in the information content of carotenoid- and melanin-based ornamental plumage: empirical tests in two cardueline finch species

Kevin McGraw*

Cornell University (kjm22@cornell.edu)

Many male birds Display striking color patterns in their feathers to communicate important messages to potential female mates or rival males. Males often use their beautiful ornaments to indicate their health, competitive motivation, or their ability to care for offspring. Because birds produce various types of color signals, these ornaments may convey fundamentally different sets of information. Red, orange and yellow colors are produced by carotenoid pigments that are obtained in the diet and deposited in feathers, whereas blacks and browns result from melanin pigments produced internally. Thus, carotenoid pigmentation should be a valuable index of nutritional condition, and melanin coloration may be independent of diet and instead could indicate the social status of individuals. However, it is still uncertain whether carotenoid colors can also signal fighting ability, and whether melanins can represent male health. I tested these ideas in two finch species, and found in captive male American goldfinches that carotenoid ornamentation, but not melanin coloration, reliably indicated nutritional condition. I also found that carotenoid pigmentation in male house finches inadequately predicted their competitive ability during winter. These two studies provide strong support for the notion that different types of plumage coloration signify entirely different aspects of mate quality in birds. (Communication 1, Wednesday 10:45 AM - 11:00 AM, NMM1)

203 Scent marking and aggression: are they correlated?

Stephen G. Mech* & Aimee S Dunlap-Lehtila*

University of Memphis (smech@memphis.edu)

We tested the hypothesis that scent marking and aggressive interactions measure the same form of dominance. To test this hypothesis, we performed three experiments using the prairie vole (Microtus ochrogaster). First, we paired 64 males and performed scent-marking and agonistic trials on each pair and found no correlation between the two measures of dominance. In the second experiment, we paired 42 males and performed scent-marking tests immediately before and after an agonistic test. The results from this experiment showed no correlation between the agonistic and either scent-marking test, but the two scent-marking tests did correlate. This suggests that direct short-term interaction does not change scent-marking patterns. The third experiment used two groups of six males each. We performed scent-marking and agonistic interaction tests before and after placing the males into enclosures for extended periods of time. Overall, the only significant correlation between measures was the agonistic interactions before and after placement in the enclosures. Together, these data suggest that scent-marking and agonistic interactions do not measure dominance the same way. We conclude that comparison of results between different studies that use different measures of dominance requires extreme caution. (Dominance & Resource Defense, Tuesday 10:15 AM - 10:30 AM, NMM2)

205 Environmental Enrichment and Behavioral Development of Orange-wing Amazon Parrots amazona amazonica

Cheryl L. Meehan*, Joy A. Mench, James R. Millam, & Joseph P. Garner

University of California - Davis (clmeehan@ucdavis.edu)

Birds are the third most popular companion animals in the United States. Parrots, in particular, are highly desired as pets because of their colorful plumage, their ability to mimic and their keen intelligence. As more and more people bring these birds into their homes as pets, it is becoming evident that keeping a pet parrot is not an easy task. Parrot owners commonly complain that their pets perform behaviors such as feather plucking, aggression, self-mutilation, incessant screaming and abnormal repetitive behaviors. We believe that the environment in which captive parrots are housed may contribute to the development of these behaviors. In our work, we study parrots that are housed in an environment that resembles typical pet caging and parrots that are housed in cages that provide an opportunity for the parrot to use its foraging skills to obtain food as well increased physical activity. We found that birds from these modified, or enriched, cages are less fearful and aggressive toward strangers, less fearful of new objects in their cages and less likely to develop abnormal repetitive behaviors. We are currently exploring the effects of an enriched environment on cognitive abilities and feather plucking. In cases where no physiological cause can be found for the abnormal behaviors that frustrate pet owners, appropriate changes to the parrot's environment may offer a solution. (Applied Animal Behavior, Tuesday 11:45 AM - 12:00 PM, Sale)

206 Morphological Analysis of Swordtail Vertical Body Bars and Implications for Female Mate Choice

Justin W. Merry* & Molly R. Morris

Ohio University (jm703496@oak.cats.ohiou.edu)

Males of many species in the genus Xiphophorus have vertical body bars on their flanks that are important communication signals in these fishes. Females of many species use the vertical body bars to judge the attractiveness of males. Therefore, they are often important signals in species recognition. Surprisingly, two species, X. birchmanni and X. malinche, interbreed in the wild, even though they have markedly different bar morphologies. A quantitative morphological analysis was conducted on the body bars of these two species, and the differences found in this analysis were used in female mate choice tests to determine whether or not they are important in female mate preference in these two species. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

207 Does food distribution affect male California ground squirrel aggressive behavior?

Vered Mirmovitch*

University of California, Riverside (melamed@keyway.net)

Ecological factors such as food distribution can affect space use of animals and consequently, might affect the frequency of aggressive interactions between individuals and their neighbors. In this study the frequency and duration of aggressive encounters between males were compared among two unmanipulated squirrel populations which served as controls, and four populations that received one of two food distribution treatments (even and clumped supplemented food distributions). Analysis of direct observation showed that clumping of food resulted in an increase in both the frequency and the time males spent on agonistic interactions. In even and clumped food supplemented populations, interactions between an aggressor and a subordinate took place significantly closer to the aggressor’s home burrow (20.1 and 24.4 m, respectively) relative to the subordinate’s home burrow (41.0 and 39.2 m, respectively). On average, the aggressive interactions occurred near the aggressor’s home range estimated borderline. It is possible that invader pressure increased due to the supplemented food and the territorial males were trying to keep other males from trying to cross their territory. The results of this study support the hypothesis that food distribution can affect aggressive behavior among males. (Dominance & Resource Defense, Tuesday 11:15 AM - 11:30 AM, NMM2)

208 Characteristics of coyote (Canis latrans) barks and howls

Brian R. Mitchell*, Michael M. Jaeger & Reginald H. Barrett

University of California - Berkeley & USDA/APHIS/WS/NWRC (bmitchel@nature.berkeley.edu)

Most dog owners know that their pet sounds different from other dogs, but surprisingly no one has studied whether coyotes have individual voices that can be used to tell them apart. Our research fills a gap in the current understanding of canid communication by showing that coyotes do indeed sound different from each other, and that there are sex-based differences in the way coyotes sound and in how often they vocalize. For example, the male coyotes we recorded were much more likely to howl without their mate than the female coyotes, and larger coyotes on average had deeper voices than the smaller ones. We are planning to apply our research to test how radio-collared wild coyotes respond to different types of vocalizations. Certain types of calls may be more likely to trigger an approach by coyotes, and others may be more likely to lead to a vocal response. Recordings of vocal responses can be analyzed to determine the number of responders and potentially even the sex or identity of specific responding coyotes. (Communication 2, Wednesday 1:45 PM - 2:00 PM, NMM1)

212 A polymorphism in female preference for vertical bars in the swordtail fish Xiphophorus cortezi.

Molly R. Morris* & Elizabeth Hesselman

Ohio University (morrism@oak.cats.ohiou.edu)

Previous studies determined that a pigment pattern of vertical bars found on male swordtail fishes functions to attract mates. Xiphophorus cortezi females prefer males with more bars, symmetrical bars and bars at higher frequencies, and yet a preference for bars over no bars had not been detected. We examined the hypotheses that there could be a polymorphism in female preference for bars, with some females preferring males with bars and some females preferring males without bars. We measured the strength of each female's preference for bars versus no bars, symmetrical bars versus asymmetrical bars and for the confounding situation of asymmetrical bars versus no bars. X. cortezi females consistently spent more time with either barred or barless males. While polymorphisms in morphological traits are commonly recognized, our data suggests that females may vary in the behavior of mate choice, preferring different types of males as mates. (Mate Choice 3, Monday 2:00 PM - 2:15 PM, NMM1)

213 Influence of Individual and Social Organizational Factors on Patterns of Allomaternal Care in a Wild Troop of Squirrel Monkeys (Saimiri sp.)

Larkspur S. Morton*

Colby College (lsmorton@colby.edu)

Although infant caretaking has been well studied in captive colonies of squirrel monkeys and caretaking behavior by non-mothers is widely reported to occur in captivity, data from field studies are lacking. A study of a habituated squirrel monkey troop in Manu National Park in Peru revealed extensive allomaternal behavior by females without same-year infants. The infant caretaking was expressed by all non-maternal females in the study group. However, young pre-reproductive females and females with infant losses retrieved and carried infants significantly more than other adult females. Several adult females were also observed to nurse their charges. Adult and juvenile females in the troop were dye-marked and individually identified, making it possible to examine clique membership in relation to infant caretaking. Results showed that non-mothers carried infants of mothers in their own clique significantly more than would be expected by chance. Additionally, observations of coordinations and solicitations for infant caretaking between mothers and non-mothers involved only specific individuals within cliques. These patterns of caretaking and coordination suggest that allomaternal behavior in squirrel monkeys is more than simply a by-product of general female interest in infants. (Regular Poster Session, Tuesday evening, Gym)

216 Territoriality in a cannibalistic predator

Jordi Moya-Laraño* & David H. Wise

University of Kentucky (jmoya2@pop.uky.edu)

Defense of territories against intruders of the same species is widespread among animals. In some predators, killing and eating other members of the same species --- cannibalism --- occurs frequently in nature. Are cannibalistic predators also territorial? This question is hard to answer, because cannibalism alone could explain the disappearance of individuals of the same species from an area. The Mediterranean tarantula, a conspicuous and colorful burrowing wolf spider, is a cannibalistic predator. The spatial pattern of burrows suggests that this species might be territorial. We tested this hypothesis by manipulating burrow distances and inducing encounters between adult females in nature. We discovered that adult female tarantulas defend territories by excluding other females, often by killing and feeding on them. Cannibalism occurs only after territorial fights have escalated and a contest escalates more likely if both spiders are of similar size. This is the opposite of what would be expected if cannibalism solely were a means to capture prey. It is clear that cannibalism in the Mediterranean tarantula is a component of territorial defense. A possible evolutionary force that shaped this extreme form of territorial behavior may be the lack of prey in desert habitats. (Dominance & Resource Defense, Tuesday 10:45 AM - 11:00 AM, NMM2)

217 Age Dependent Variation in Courtship Song of Teleogryllus oceanicus

Kristin Muller* & Thomas G. Nolen

State University of New York - New Paltz (KristinMLR@earthling.net)

Male crickets produce three types of vocalizations: Calling, rivalry and courtship songs. While calling song is used to locate the singer from a distance, the rivalry and courtship songs are used for more proximal interactions. Several researchers have reported differences in calling song characteristics between populations of Teleogryllus oceanicus in areas with different levels of parasitism by Ormia ochracea (e.g., Zuk et al, 1996; Simmons and Zuk, 1994). These observations may be due to differences in the competing selective pressures on survival (avoiding attracting parasitoids) and sexual selection (driven by female cricket song preference), or to age dependent results caused by increased mortality of older males who vary in singing ability. To test for age dependent effects on singing we paired male Teleogryllus oceanicus with sexually mature females and recorded their interactions on digital video and audio tape. We have begun to define the range of variation in the male's vocalizations during these interactions. Since older males are more likely to incur risks, we plan to compare the characteristics of these songs as a function of age. (Regular Poster Session, Tuesday evening, Gym)

218 Dinosaur nest ecology and predation during the late Cretaceous: Is there a relationship?

Stephen J. Mullin*, John Bois & Robert J. Cooper

Eastern Illinois University, Northwestern High School & University of Georgia (cfsjm@eiu.edu)

We suggest that an increased diversity of mammalian and avian egg and hatchling predators played an important role, among other contributing factors, in the extinction of non-avian dinosaurs. We argue that dinosaurs were predisposed to reproductive failure because they nested in exposed locations that they were obliged to actively defend. Further, we provide evidence supporting the hypothesis that this strategy has seldom been practiced in the Cenozoic because it is viable in few habitats. We suggest the evolution of large size among avian species has been constrained by nest and hatchling predators, the largest species being limited to either grasslands (a biome not available to non-avian dinosaurs), wetlands (a biome which was greatly reduced at the Cretaceous/Tertiary boundary), and places with low predation pressure, particularly from mammals (e.g., New Zealand). (Regular Poster Session, Tuesday evening, Gym)

219 Seasonal patterns of reproductive investment in guira cuckoos

Laura S. B. Muniz* & Mariana O. Cariello

Universidade de Brasília (lauramuniz@hotmail.com)

South American guira cuckoos (Guira guira) breed communally, with several females contributing clutches to a joint nest. Ecological factors may affect individual and communal clutch sizes, interval between repeated nestings, and egg and nestling elimination by group members. Because opportunities to reproduce halt at the end of the rainy season, we predicted that: (1) egg volume and total clutch size would increase within seasons; (2) ovicide and infanticide would be higher in the beginning of the season; (3) interval between repeated nestings would decrease; and (4) egg laying interval to complete communal clutches would decrease. We found that, as the rainy season progresses, there is a slight increase in egg volume; and that the interval between repeated nestings shortens. No other seasonal effects were found for other reproductive variables. The destructive components of reproduction in this species (ovicide and infanticide) may be somewhat independent of ecological variables, and more sensitive to social dynamics within groups. On the other hand, egg production variables may be influenced more strongly by ecological and/or physiological conditions. (Regular Poster Session, Tuesday evening, Gym)

220 Mate sampling by female barking treefrogs

Christopher G. Murphy*

James Madison University (murphycg@jmu.edu)

Male animals often have bright plumage, demanding courtship Displays, and loud calls, whereas females less commonly exhibit these traits. One explanation for this difference is that males with such traits are more likely to be chosen as mates by females than are dull or less vigorously Displaying males. Much is known about which traits influence females' choice of mates, but little is known about how females gather information about prospective mates. This study examined how female barking treefrogs investigate potential mates. In this species, males produce loud, rapid calls, and females base their choice of mates on the quality of these calls. In natural choruses, females do not move from one male to the next, inspecting each male in turn. Instead, females approach the chorus, stopping often to listen to males. When females are close to the chorus, they stop and listen to a few of the closest males and pick the best male from this group. Experiments in which females were presented with speakers broadcasting artificial calls provide further evidence for this method of gathering information about prospective mates. This mechanism may be more common in animals than previously thought. (Mate Choice 4, Wednesday 9:45 AM - 10:00 AM, NMM2)

222 Fleeing, freezing or dying: Influence of temperature and physical condition on the antipredator behavior of a hylid frog, Scinax hiemalis

Carlos A. Navas, Fernando R. Gomes & Catherine R. Bevier*

University of Sao Paulo & Colby College (crbevier@colby.edu)

Antipredator behavior may be influenced by ecological factors, such as ambient temperature and predation pressure, and by intrinsic factors, such as physiological condition. We tested the hypothesis that both types of factors interact to induce a particular antipredator response in the treefrog, Scinax hiemalis. This species exhibits a passive response by either feigning death or freezing, or an active escape response when disturbed by predators. We examined the responses of 24 adult male S. hiemalis to simulated predation in the laboratory at 10, 15 and 20C. In addition, responses from a single stimulus were compared to those from a series of stimuli. We determined physiological condition from measures of body length and mass, jumping performance, aerobic metabolic scope, and estimated energy reserves. Temperature had the most influence on antipredator behavior, with more frogs exhibiting passive responses at 10C than at higher temperatures. If stimulated more than once, the proportion of active responses increased at all three temperatures. Larger individuals were more likely to exhibit an active response, but no mass-independent physiological variables were related to response type. These results suggest that frogs respond to both extrinsic and intrinsic factors that may affect their behavioral performance. (Anti-predator Behavior, Tuesday 5:00 PM - 5:15 PM, NMM2)

224 Classification of domestic cat vocalizations by naive and experienced human listeners

Nicholas S. Nicastro*

Cornell University (nn12@cornell.edu)

The long history of human cohabitation with domestic cats offers the possibility of testing the effect of artificial selection on signaling behavior. Based upon exposure to recordings of single vocalizations (meows) obtained under controlled conditions, human subjects in this study performed a forced-choice classification task between five behavioral contexts of vocal production. The contexts ranged from affiliative, agonistic, distress, to food- and obstacle-related. Subjects also rated their degree of familiarity with cats along three different scales. Responses were scored for accurate classification of both the context of call production and of the affective tone of the calls, positive or negative. The results show an effect of experience on call classification, with familiar human subjects outperforming naive ones on both the context and affect measures. There is also evidence of a differential effect of familiarity: where reading of affect shows only a modest positive correlation with experience, classification of context improves more sharply. We therefore suggest that the former is based on a general pattern of affect communication in mammals, and that the learning of higher-order classifications is in turn "scaffolded" upon that pattern. (Communication 2, Wednesday 2:00 PM - 2:15 PM, NMM1)

225 Deducing the migratory status of a secretive, nocturnal owl, the Flammulated Owl: hypotheses and data needs.

Barry A. Nickel* & D. Archibald McCallum

San Francisco State University & College of Charleston (sfbaffo@aol.com)

The Flammulated Owl (Otus flammeolus) is an environmentally sensitive, insectivorous species that occupies commercially valuable ponderosa pine (Pinus ponderosa) forests in the western United States. Little is known of its winter range, and some authorities speculate that it winters near breeding grounds rather than migrating to Mexico, as is usually assumed. To conservatively test this migratory ambiguity, we erected a series of hypotheses to address the possible existence of alternative migration strategies. We collated 379 specimen or photographic records and 756 published records (not substantiated by specimens) from the U.S. and Canada. We predicted a positive correlation between latitude and the Julian dates at which Flammulated Owls were first encountered in the spring and a negative correlation between latitude and the Julian dates of last encounter in the autumn. Although our prediction of a correlation between latitude and date appears supported for the spring, fall records are rather uniformly distributed in this respect. We cautiously interpret this asymmetrical pattern as suggesting that some individuals indeed attempt to overwinter in the north, but few survive. With the evidence provided or available, we conclude that this species probably migrates latitudinally, but the occurrence of altitudinal and partial migration cannot be completely refuted. In lieu of all the distributional records analyzed here, the study of molecular genetic variation across the range of the species using modern techniques could better answer the question of Flammulated Owl migration. (Regular Poster Session, Tuesday evening, Gym)

226 Risky Business? Acoustic Elements of the Courtship Song of Teleogryllus oceanicus

Thomas G. Nolen* & Kristin Muller

State University of New York - New Paltz (tomnolen@mad.scientist.com)

It is not known if female crickets use differences in male courtship songs to choose a mate. However, certain components of the male's courtship song are important for his mating success. One possible function of the male's courtship song is as an indication of his ability to incur the risk of attracting both parasites as well as rival males. If this is true in Teleogryllus oceanicus, the trill of the courtship song should be similar to that of the calling song, which is attractive to male crickets (Pollack, 1982). Conversely, the chirp of courtship should be similar to that of the calling song, which is attractive to parasitoid flies. Using digital audio and video analysis we are comparing the song components the male presents during successful vs. unsuccessful courting attempts. Since older males are more likely to accept risks, we also plan to compare the characteristics of these songs as a function of his age. (Regular Poster Session, Tuesday evening, Gym)

228 General Ecology and Behavior of the Black Howler Monkey, Alouatta pigra, in the Pristine Site of Irish Creek, Belize.

Araba P. Oglesby* & Hal Markowitz

San Francisco State University (OglesbyA@aol.com)

A general ecology and behavior study was conducted in the protected old growth forest of Irish Creek, Belize. Transects were established for a black howler monkey habitat survey, population census, and behavior assessment in a 1.5 x 2.5 km block of varying seasonal forest. Approximately 25 troops occupied a variety of habitats, ranging from swamp to lowland moist evergreen forest. Activity budgets were comparable to previous data gathered on the species with 62% of daily time spent resting, 17% feeding, 14% vocalizing, 7% traveling and 1% urinating/defecating. High percentages of vocalization may be partly due to human presence. Average troop size was 6-7 individuals with a maximum of 16 howlers in a troop. Many multi-adult male troops were observed, possibly because of high resource availability and moderate amounts of natural predation. At least 2 troops of spider monkeys, Ateles geoffroyi, also inhabited the site, allowing interactions with a sympatric species. With the habitat of this threatened black howler species increasingly fragmented, the conservation implications of maintaining protected sites such as Irish Creek are of great concern. (Applied Animal Behavior, Tuesday 2:00 PM - 2:15 PM, Sale)

229 Female mate choice based on male behavioral characteristics in Domino Damselfish, Dascyllus albisella

Steven James Oliver*

Boston University (sjoliver@bio.bu.edu)

For terrestrial vertebrates, acoustic courtship (e.g. bird song, frog chorusing, and elk bugling)is a familiar and well studied phenomenon. Acoustic courtship in fishes is less familiar, and less obvious to the casual observer. As such, it has received less scientific scrutiny than other taxa. We used a tagged population of male and female Domino Damselfish (Dascyllus albisella)(Pisces: Pomacentridae) to measure reproductive success of males based on acoustic cues. Typical cues of male size, male age, and territory quality were not correlated to male mating success. However, the rate of male calls was a significant indicator of male reproductive success. At present, there is no evidence to suggest that males are producing significantly different coutship calls. It appears that the number of calls and the repetition rate are the cues most used by females in selecting mates. Clearly, human impacts on the acoustic environment of these common reef fish could have conseqences to their reproduction. (Mate Choice 2, Sunday 2:15 PM - 2:30 PM, NMM2)

232 The winner effect in Peromyscus mice

Temitayo O Oyegbile* & Catherine A. Marler

University of Wisconsin-Madison (oyegbile@students.wisc.edu)

How an animal approaches an aggressive encounter can be heavily influenced by the results of previous encounters. Therefore, an animal can be more likely to lose an encounter if it recently lost an encounter (loser effect) and can be more likely to win an encounter if it recently won an encounter (winner effect). We are testing the likelihood of winning a future (final) aggressive encounter after winning three, two, one or no resident-intruder encounters in the mouse _Peromyscus californicus_. During the initial encounters, the resident males are more likely to win encounters because the intruders are mildly sedated. During the final encounter, residents are less likely to win because the intruders are also previous winners and larger in size. Lastly, we are comparing the territorial P. californicus to a less territorial species, P. leucopus, to determine if the winner effect is associated with territoriality. Testosterone levels will also be compared between groups. Preliminary results suggest that the winner effect increases depending on the number of aggressive encounters an individual has experienced and that the winner effect can occur in rodents. (Regular Poster Session, Tuesday evening, Gym)

233 Discrimination among predatory gull species by common terns Brian G. Palestis* & Joanna Burger Rutgers, the State University of New Jersey (palestis@eden.rutgers.edu) Gulls, whose populations have increased greatly, are often predators on tern eggs and chicks, and compete with terns for nesting sites. We studied the nest defense behavior of common terns (Sterna hirundo) versus three species of gulls, over three years. At other tern colonies, herring gulls (Larus arentatus) have been the gull representing the largest threat to terns, and terns biased their nest defense toward this species. At our field site, a pair of great black-backed gulls (L. marinus) nested among the terns, and were the only gull species seen preying on tern young. Terns responded to great black-backs more frequently than to other gulls, regardless of the behavior of the gull. Responses to great black-backs were also more aggressive and caused more terns to fly up from their nests than responses to herring and laughing gulls (L. atricilla). The behavior of common terns thus appears quite flexible, as responses to predators vary with the threat posed by particular species at a particular site. (Regular Poster Session, Tuesday evening, Gym)

234 Predator-prey interactions: Behavioral responses of an estaurine fish to predator signals Kristian Parker* & Daniel Rittschof Duke University (kkp1@duke.edu)

Predator-prey interactions based on sensory information are limited by physical constraints on sensory transmission. Prey responses are therefore dependent upon environmental context. Context changes constantly in estuarine environments. Flow rate and direction, turbulence and turbidity, temperature, salinity and structural complexity change continuously with the tides. If one overlays this dynamic with migratory predators that are both nocturnal and diurnal, it is clear that the level and importance of sensory information available to prey is constantly changing. This study describes the response of an estuarine fish, Fundulus heteroclitus, to chemical and visual predator cues. We describe responses to visual and chemical cues and their interaction in the laboratory. While visual cues depend upon light level, responses to chemical cues are independent of light levels and stereotyped. Responses to cues depend on the order of presentation. The cue received first, suppresses or alters the response to the second cue. Interaction between cues can be measured as a change in the absolute level of responsiveness. Predator-prey interactions should be considered in several sensory modalities, especially when dealing with highly dynamic habitats. (Anti-predator Behavior, Tuesday 4:45 PM - 5:00 PM, NMM2)

238 The relationship between sex ratio and the gonadosomatic index in adult male, free-ranging Milne-Edward’s sifakas (Propithecus diadema edwardsi) in Ranomafana Park, Madagascar

Sharon T. Pochron*, Patricia C. Wright, Edward Schaentzler, & Michael Ippolito

State University of New York - Stony Brook (spochron@ms.cc.sunysb.edu)

Some adult male sifakas have really large testicles compared to others, even after body weight and season is accounted for. We wanted to see if social factors could explain these differences. Sperm competition theory predicts that as groups gain males, males should grow larger testicles. We used 12 years of behavioral and morphometric date to test this prediction. Contrary to sperm competition theory, as male groups become more male biased, males get relatively smaller testicles, and as the sex ratio became more female biased, males grew relatively larger testicles. This implies that females in this seasonally breeding primate may monopolize sperm. In support of this, as the breeding season approaches sifaka groups become less female biased and the number of females decreases. Looking at groups containing either one breeding female or two, we expected to find relative testicle size to increase as the sex ratio became more male biased. In both groups we found the opposite. Furthermore, as male rank increased, relative testicle size increased; male rank was assigned according to how much time they spent near females rather according to male-male aggression. Rather than male-male competition for access to females driving variation in relative testicle size, it appears that female monopolization of sperm drives it. (Social Behavior 2, Tuesday 5:30 PM - 5:45 PM, NMM1)

240 Aggression in Dogs Elicited Through the Use of Electronic Pet Containment Systems Richard H. Polsky* (absc@ladogtraining.com)

Applied animal behaviorists serving dog owners have made note of the possible connection between a dog's experience of electronic shock and the elicitation of aggression. Nonetheless, most dog owners remain ignorant of the possibility that aggression in a dog can be elicited due to the pain caused by an electronic shock collar, particularly the kind that are used in boundary training. Boundary training collars are widely used by the dog-owning public. To this date, no report exists in the veterinary or animal behavior literature which focuses specifically on the fact that electric shock can cause some dogs to become aggressive. In this report, I report seven cases where electric shock delivered from a training collar was the principal cause underlying a dog's attack on a human. Data from each case is presented. Pros and cons of the use of electronic collars as training devices in behavioral modification for dogs are discussed. (Applied Animal Behavior, Tuesday 1:45 PM - 2:00 PM, Sale)

241 Cooperative infant care by Greater Spear-Nosed Bats Teresa A. Porter* University of Maryland (tp35@umail.umd.edu)

Despite the large number of published studies examining cooperation, few have documented cooperation among unrelated individuals. Greater spear-nosed bats (Phyllostomus hastatus) provide a favorable system for examining cooperation without relatedness. Although female groupmates are not closely related to each other in this species, they often remain with the same social group for decades, in which they forage cooperatively and give birth synchronously. Over two birth seasons, I videotaped six wild groups in a cave on Trinidad, West Indies, and two captive groups at the National Zoological Park, Washington, DC. Each group comprised eight to 25 females that shared a roosting cavity with their singleton pups and only one adult male. When most of the mothers departed the cave at night to forage, they left their pups behind, often clustered with one or more lactating mothers in the group. I will address patterns in the cooperative behaviors of these mothers that stayed behind, as well as the characteristics that predicted which mothers groomed the pups of their groupmates, nursed them, and retrieved them from nearby spots on the cave ceiling. Supported by NICHHD fellowship 5 F32 HD07928-03 and NSF grant IBN-9209401. (Regular Poster Session, Tuesday evening, Gym)

243 Memory for food caches and unpredictable food in mountain chickadees

Vladimir Pravosudov* & Nicola Clayton

University of California - Davis (vpravosudov@ucdavis.edu)

Food-caching birds wintering in temperate climate rely on two sources of energy for their survival: internal body fat and external food caches. Whereas access to body fat is unlimited, caches may not be recovered for hours, days or even months. Birds rely on spatial memory to recover previously hidden caches. Failure to find caches may potentially result in death from starvation. Cache recovery may be more critical for birds that forage in harsh conditions than for those foraging in mild conditions. We hypothesized that birds should have a better spatial memory and be more accurate at recovering their caches when food is limited and variable. To test our hypothesis, we compared the cache recovery behavior of 24 wild-caught mountain chickadees (Poecile gambeli). Half of the birds were maintained on limited, variable food and the rest were maintained on unlimited food for 60 days. We then tested their spatial memory by allowing birds form both groups to cache food in the experimental room and then recover their caches 5 hours later. Our results indicated that birds maintained on variable food made significantly fewer mistakes when recovering their caches compared to birds maintained on unlimited food. (Animal Learning & Cognition, Tuesday 9:45 AM - 10:00 AM, Sale)

248 Association patterns of resident and non-resident bottlenose dolphins (Tursiops truncatus) in the Cedar Keys, Florida

Ester Quintana-Rizzo* & Randall S. Wells

Chicago Zoological Society (quintana@mote.org)

Little is known about the social organization of bottlenose dolphins in open estuarine systems. Our purpose was to identify and quantify the associations formed among bottlenose dolphins to provide insights into the social organization of the species in the open estuarine system of the Cedar Keys, Florida. Monthly photographic-identification surveys were conducted from June 1996 through May 1997. Surveys were standardized to cover the entire study area, and survey routes were used to minimize a heterogeneous sampling. Resightings of identifiable dolphins were used to determine whether individuals were residents or non-residents, and to quantify associations. A dolphin was considered a resident if it was seen more than 6 months, and a non-resident if it was seen between one and five months. Of the 219 individual identifiable dolphins, 41 were characterized as residents and 170 were characterized as non-residents. Associations between residents and non-residents were mostly loose, and did not show any pattern between individuals of different gender or reproductive condition. In contrast, associations among residents were higher within sexes than between sexes. Associations among males and among females appear to result from individual preferences. Associations may provide a greater protection from open water predators, and a greater access to mates. (Social Behavior 2, Tuesday 5:00 PM - 5:15 PM, NMM1)

249 Can generalist predators be 'induced' to prefer chemically defended prey? Behavioral choices by predatory adult and larval paper wasps.

Linda S. Rayor*, Steve Munson, Monica Lee & Jennifer Chow

Cornell University (lsr1@cornell.edu)

Predatory paper wasps capture a wide range of caterpillars, many of which are chemically defended, that they feed to their developing wasp larvae. We have been interested in what factors affect the wasps decision to capture or avoid chemically defended caterpillars. Newly emerged adult paper wasps are naive foragers, but may have experienced plant defensive chemistry in their larval diet. Our experiments were designed to determine how the foraging choices of adult wasps were affected by what they had consumed as larvae. In addition, we observed the behavior of feeding wasp larvae to determine whether larval rejection of prey containing plant defensive chemicals provided proximal cues that affected the forager's choice of prey. Our research uniquely demonstrates that predatory wasps choices of caterpillar prey are dramatically affected by their individual experience and by subtle feedback from feeding larvae on the nest. (Predator Prey, Monday 1:30 PM - 1:45 PM, NMM2)

250 Prospecting for breeding sites on a landscape scale: empirical patterns and population dynamic consequences

J. Michael Reed*

Tufts University (MREED@TUFTS.EDU)

Dispersal is key to population persistence in large or fragmented habitats. Typically dispersal is treated by population modelers as a mechanical process, or a faucet, with X individuals going Y distance. However, dispersal in many species is a behavioral process, whereby animals gather information prior to breeding and use the information to make decision about where to breed. Studies of birds show evidence that some species gather and store information on potential breeding sites (often called prospecting) for 9 months or more before breeding. Incorporating behavior into predictive models will improve their accuracy, particularly in fragmented habitat. I review empirical evidence for prospecting and discuss the patterns and implications to population dynamics. These behaviors also might be used as conservation tools for starting new breeding sites or increasing the number of breeders. (Dispersal Symposium, Sunday 3:00 PM - 3:30 PM, Sale)

251 Avoidance learning in companion animals: from laboratory to the real world.

Pamela J. Reid*

University of Guelph (preid@ovcnet.uoguelph.ca)

Behavior problems in dogs and cats are very common. Many owners become frustrated with their fearful or aggressive pets. These behavior problems often arise because the animal perceives that it is in uncomfortable or dangerous circumstances. For instance, a dog that fears having its nails clipped may snap at you if you ask it to shake a paw. Applied animal behaviorists are skilled with helping owners rehabilitate their pets because of their extensive knowledge of how animals alter their behavior in response to the changing demands of the environment. Real-world case studies provide demonstrations of how behavior modification techniques work to eliminate undesirable behavior and enhance the relationship between pets and people. (Applied Animal Behavior Symposium, Tuesday 3:45 PM - 4:15 PM, Sale)

254 Scaling the depths of hypoxia: Do smaller fish have a greater tolerance to oxygen depleted waters?

Tonia Robb* & Mark V. Abrahams

University of Manitoba (umrobbtl@cc.umanitoba.ca)

Within a fresh water environment hypoxic (reduction in dissolved oxygen) areas can occur as a result of an abundance of plant material as well as increase in temperature and pollution. We set out to determine if smaller fish have a greater tolerance to hypoxia and subsequently use these hypoxic habitats as a refuge from larger fish predators. Tolerance was determined by measuring blood variables indicating the oxygen carrying capacity of the blood as well as the ability of the fish to maintain water flow over the gills (ventilation frequency). We developed a model based on this size specific relationship to predict the distribution of both a predator (yellow perch) and prey (fathead minnow) population in an environment with fluctuating dissolved oxygen. The decision to enter the habitat was defined by the costs and benefits of entering. All of the physiological variables measured suggested a size sensitive relationship in which the smaller prey were better able to withstand hypoxic conditions. These data, in combination with our model suggest our hypothesis that hypoxia can generate predator-free refuges. (Habitat Choice, Monday 4:15 PM - 4:30 PM, Sale)

255 Prolactin influences alloparenting in Common Marmosets

R. Lucille Roberts*, Theodore Lawler, Kosunique T. Jenkins & John D. Newman

Laboratory of Comparative Ethology, National Institute of Child Health and Human Development (lroberts@zool.umd.edu)

The neuroendocrine mechanisms for alloparental behavior (parenting another's offspring) are poorly understood. Alloparenting is ubiquitous among human cultures, but rare in non-human primates. New World primates of the family Callitrichidae are an exception. Callitrichids, including common marmosets, dwell in nuclear families and all family members help care for infants. This study tested the hypothesis that prolactin, an adenohypophysial hormone correlated with alloparenting in many birds and mammals, promotes alloparental responsiveness in common marmosets. Parentally naive adult common marmosets (Callithrix j. jacchus) were tested repeatedly for infant retrieval and carrying. Ten of the 14 marmosets retrieved by the fourth test and the four monkeys failing to retrieve never retrieved infants in ten tests. Serum prolactin concentration was significantly correlated with carrying time and was significantly elevated after infant-exposure only in the alloparentally responsive monkeys. Bromocriptine administration reduced serum prolactin to undetectable levels and was associated with significantly reduced frequency of infant retrieval and mean carrying time. We conclude that alloparental responsiveness is a stable trait after initial effects of novelty are overcome. High prolactin levels are important for alloparental responsiveness in common marmosets. (Parental Care 2, Sunday 2:15 PM - 2:30 PM, NMM1)

256 The Ecology of Payoffs in a Producer-Scrounger System

Renee L. Robinette*

University of Washington (robinet@u.washington.edu)

When Northwestern crows feed on the beaches of Puget Sound, they use two different strategies to obtain food. Individuals called producers, find their own food (clams, mussels, shorecrabs, worms and intertidal fish), while individuals called scroungers steal food found by producers. If behavior is influenced by natural selection (a process whereby evolution occurs), then individuals should make decisions about how to feed that results in maximizing their caloric intake or minimizing their risks of starvation. How can individuals using two very different behavioral strategies have the same caloric intake? If the entire population of beach-foraging crows were trying to eat by stealing food from other crows, then there wouldn't be any individuals who were finding food! Instead, individuals base their use of each strategy on how many other individuals are producing or scrounging food, and they switch back and forth between the two strategies all the time. If an individual could get more calories by switching from scrounging back to producing, they do so. The end result is that the strategies are equally successful, and most of the time the birds do what will get them the most calories. (W.C. Allee Competition, Monday 2:30 PM - 2:45 PM, Sale)

257 Sensory bias and the evolution of female choice in wax moths

Rafael L. Rodriguez S.*

University of Kansas (rafa@falcon.cc.ukans.edu)

The evolution of female choice may occur by means of selection on females to obtain resources or good genes for themselves or their offspring. But it may also occur by means of selection in a non-reproductive context. That is, from the point of view of choosing mates, female choice may be an adaptation or a by-product. I tested a prediction designed to make this distinction in wax moths. Moth hearing evolved to detect bat echolocation calls, but in wax moths it is also used in pair formation. Males produce ultrasonic calls that females prefer if they have a high signal rate. If this female trait is a by-product of selection for bat evasion, there should be a correlation between the responses of females in both contexts. I obtained the minimum signal rates of male and bat calls to which females responded with phonotaxis or evasive flight manouvers, respectively. Female responses were not correlated. Thus, female choice in wax moths appears to be an adaptation in the reproductive context. (Evolution of Signals, Tuesday 9:45 AM - 10:00 AM, NMM1)

258 A comparison of vocalizations in American Crows and Fish Crows

Ruby Rose & Jeffrey A. Cynx*

Vassar College (chaos@vassar.edu)

Crows are one of the most common songbirds people see and hear. They produce a number of learned vocalizations. However, we have little understanding of the function of these calls, whether they serve to let other crows know the location of the caller, to ward off intruders, or to attract mates. As a first step in understanding their vocalizations, we determined that there were major differences, when comparing such properties as call duration and harmonic intervals, between the vocalizations of the two species in eastern New York state. (Communication 2, Wednesday 2:15 PM - 2:30 PM, NMM1)

261 Eye size, vision, and behavior in butterflies

Ronald L. Rutowski*

Arizona State University (r.rutowski@asu.edu)

Many physiological functions and mechanical properties of animal bodies that influence behavior vary with body size both within and between species. In this talk I will explore how eye structure might change with body size in arthropods and the implications of these changes for vision and for behavior. Data comparing the structure and optics of four species of butterflies that range from 17 to 80 mm in forewing length suggest that while visual field size changes little with body size, larger butterflies should be able to detect members of their species at much greater distances and at lower light levels than smaller species. I will discuss the implications of these effects of body size on vision for our understanding of the behavioral ecology of butterflies and other arthropods. (Communication 1, Wednesday 10:30 AM - 10:45 AM, NMM1)

263 Mechanisms behind mate choice of male convict cichlids

Nick Santangelo* & Murray Itzkowitz

Lehigh University (Ni55@lehigh.edu)

Very few mate choice studies are concerned with males of monogamous species. Our previous studies have shown that females prefer to spawn with larger males and show a continuous assessment of available individuals. How males distinguish between potential mates in the absence of female-female interactions was studied using convict cichlids (Archocentrus nigrofasciatum formerly Cichlasoma nigrofasciatum). Males were placed in tanks in which they had access to two individual females that did not have contact with each other (visual or tactile). Females varied in quality (size is correlated to quality in convict cichlids), and males had the opportunity to spawn with either of them. The male choice process will be discussed and compared to the female choice process. (Mate Choice 4, Wednesday 10:45 AM - 11:00 AM, NMM2)

264 Activity Pattern of the Black Howler Monkey, Alouatta pigra, and the Influence of Environmental Factors on Habitat Choice in Lamanai, Belize

Patricia Schick*, Araba P. Oglesby, Brenda Salgado & Hal Markowitz

San Francisco State University (pschick@sfsu.edu)

A group of black howler monkeys was studied over a three-month span during a dry season at Lamanai, Belize. The site served as a semi-forested corridor for two migrating howlers, and as a home for two human-reared juveniles. During this study, a daily activity pattern was determined for black howlers at Lamanai, as well as an analysis of the effects environmental variables have on habitat selection. The habitats which the howlers chose to occupy were broken down into five segments of different qualities. A greater percentage of time was spent in segment 5 (29.5%), a habitat of excellent quality with various fruiting and leafy trees of different heights. The activity budget of black howlers at Lamanai yielded percentages of 62.7% (rest), 17.0% (feed) and 15.0% (travel). These results were consistent with data observed at different sites with comparable habitat. Significant correlations were observed between the pair of migrating howlers with respect to resting, traveling, feeding and vocalization. Howlers show a significant preference for certain habitats based on our findings. (Regular Poster Session, Tuesday evening, Gym)

265 Temperature avoidance behavior of the American lobster (Homarus americanus) at ambient winter temperatures.

Suzanne M. C. Schreiber* & Winsor H Watson III

University of New Hampshire (suzanne@cisunix.unh.edu)

The Great Bay estuary is home to a migratory population of American lobsters. Trapping studies have shown us that, while there are equal numbers of adult male and female lobsters at the mouth of the estuary, there are as many as five times more adult males than adult females in the upper reaches! Using the estuary as a habitat provides many benefits to lobsters because it is much warmer than the coast. So, why are only males taking advantage of these benefits? Some previous research shows that, during the summer, female lobsters are more likely than males to move out of a shelter heated up by about 8C. However, when the same experiments were performed in winter, neither male nor female lobsters would move. This makes sense, because if you heat water by 8C in the summer, it will approach lethal for lobsters, but if you heat it the same amount in winter, it will be just about perfect! We wanted to see if winter lobsters would avoid water heated beyond their preferred range. Our results showed that winter lobsters will move away from areas at a lower average temperature than is necessary to make summer lobsters move. (Habitat Choice, Monday 5:00 PM - 5:15 PM, Sale)

267 Influence of status and time outside on estrous cyclicity in captive elephants

Bruce Alexander Schulte*, Elizabeth Feldman, Ruth Lambert, Renee Oliver & David L. Hess

Georgia Southern University (BAS) (bschulte@gasou.edu)

The captive elephant population in North America is in reproductive decline and without importation from the wild may cease to be viable within decades. The estrous cycle of three captive, reproductive age African elephants was monitored for three years by measuring serum progesterone concentrations. Each elephant experienced one or more episodes of extended low progesterone (>12 weeks), indicating a temporary period of ovarian inactivity or acyclicity. Reports of similar bouts of acyclicity exist; however, this phenomenon has not been examined in detail. In this study, the most subordinate female had the longest and the dominant female had the shortest total duration of acyclicity. During periods of acyclicity, the number of hours the elephants spent outside was significantly less than during non-luteal or luteal phases. Except in one instance, behavioral data recorded by elephant keepers during their interactions with the elephants showed no change in handling during periods of ovarian inactivity. Further study is necessary to distinguish the cause for acyclicity. Understanding this phenomenon is imperative for the future reproductive viability of captive elephant populations and will shed light on reproductive mechanisms that may operate in wild elephants. (Regular Poster Session, Tuesday evening, Gym)

268 Daily travel distances of coyotes (Canis latrans) in a temperate forest of Durango, Mexico.

Jorge I. Servin*, Carmen Huxley & Victor Sanchez-Cordero

Instituto de Ecologia, A.C. & Instituto de Biologia, UNAM (biojserv@jinx.umsl.edu)

The movements of coyotes (Canis latrans) were studied for two years (1990-1991) in a oak-pine forest area between 2,200 to 2,700 m above sea level in Southeastern Durango, Mexico. Fifteen adult coyotes (7 females and 8 males) were trapped, radiocollared and radiotelemetry data were obtained using 24-hours samples. Data were grouped into four biological seasons (breeding, gestation, pup rearing and juvenile independence). High travel activity was found; males traveled longer distances (16.47 km) than females (12.51 km) in 24-hours periods (p < 0.001). Annual mean night travel distances were longer (8.24 km) than day movements (6.51 km) (p=0.0206). Females and males traveled similar day and night mean distances in breeding, gestation and juvenile independence seasons. However, during the pup rearing season males (p=0.004) and females (p=0.025) were active preferentially at night. Locomotor activity is influenced by biological seasons, food availability in time and space, as well as individual characteristics. The daily travel distances of coyotes reflect their constant interaction with the environment; food abundance and biological seasons determine daily extent of movements. (Regular Poster Session, Tuesday evening, Gym)

269 The effect of moonlight on spatial learning in steppe ferrets

Karen A. Halley Sheffer*, Jennifer A. Clarke & Deborah R. Griffin

University of Northern Colorado (hall5684@blue.unco.edu)

We tested spatial learning abilities of steppe ferrets (Mustela eversmanni) in bright and dim moonlight. Steppe ferrets live in a relatively featureless habitat, the Siberian steppe, and often travel long distances; thus, identifying distant visual landmarks is likely important. Spatial learning trials were conducted in a hexagonal arena with 19 evenly spaced holes, one of those being the goal containing a treat. No visual or scent cues were available within the arena. External spatial cues were visible outside the arena on the ceiling and walls of the room. Trials were conducted in simulated half moonlight and then in simulated quarter moonlight. In six half moonlight trials the time required and distance traveled to locate the goal significantly decreased. In six quarter moonlight trials the time required and distance traveled to locate the goal were random. The number of times ferrets looked up at spatial cues did not differ in half moonlight versus quarter moonlight. However, ferrets looked up more in the first trial compared to later trials. These results illustrated ferrets used spatial cues to learn the goal location. It is also apparent they had difficulty learning the goal location in dim moonlight. From this study, it appears spatial learning and moonlight levels are important to these nocturnal predators and may also be important to their close relative, the endangered black-footed ferret (M. nigripes). (Regular Poster Session, Tuesday evening, Gym)

271 Dominance and grazing- a study on the Icelandic horse

Hrefna Sigurjónsdóttir* & Anna G. Thórhallsdóttir

University of Education and Agricultural University, Iceland (hrefnas@khi.is)

To work out dominance relationships within a group of horses, records were made of interactions between 15 individuals in a field and experiments with grass pellets were carried out. Nearest neighbor analyses was also done. Behavior of individuals was measured to get an estimate of time budgets. The group was regularly split and kept in 3 differently sized enclosures. The relation between each pair of horses was based on both aggressive and submissive acts. There was a significant positive relation between rank and weight and rank and aggressiveness. Most time was spent grazing and standing still. There was a significant positive relationship between weight change of individuals and size of available grazing area. Those horses which were of similar rank tended to stay together and have friendly relations. The 3 most dominant horses spent less time grazing than the others – a finding that suggests that these individuals were either dominating the best parts of the field or more efficient in feeding. (Regular Poster Session, Tuesday evening, Gym)

272 Behavioral carryovers, tradeoffs and performance correlations across situations

Andrew Sih*

University of Kentucky (ndc@pop.uky.edu)

The idea that organisms (humans, dogs, cats) have a personality can be quantified in terms of behavioral tendencies that ‘carryover’ across situations. That is, an individual is bold, as opposed to shy, if across a variety of situations, it tends to be more bold than other individuals. Or, an individual has a high activity personality if, even though it alters its activity depending on the context, its activity level remains generally higher than others across the various contexts. Although personality types are well studied in humans (and in a few other animals), behavioral carryover effects have not been examined in most other animals. We discuss some evolutionary and ecological implications of behavioral carryovers, including the possibility that they can explain mal-adaptive behavior in some contexts. We illustrate our ideas with data on feeding/antipredator behavior of larval salamanders, and on mating behavior of stream water striders – organisms that are not usually thought of as having personalities. (Behavioral Context, Monday 11:00 AM - 11:15 AM, NMM2)

274 Are all signals the same? The influence of predation intensity on signal use in a lizard

Valerie Simon*

Duke University (vbs@acpub.duke.edu)

Anolis lizards, like many other animal species, walk a fine line between mating and death. The communication signals they use to attract mates and deter rivals may also catch the eye of predators. However, these lizards communicate with a variety of signals that may not be equally visible to predators. The headbob and pushup, both used in the context of mating and territory guarding, may not enhance the visibility of the signaling lizard as much as extensions of the dewlap, a colorful throatfan. If so, do lizard populations in habitats with abundant predators evolve to use less flashy signals? Do healthy individuals, by virtue of their enhanced abilities to escape predators, communicate with flashy signals even in the presence of predators? In my study, I have developed robotic lizards to test the hypothesis that signals are not equally visible to predators. I then relate these results to observations of lizard populations that differ in their signal use, predator exposure, and prevalence of reptilian malaria. Ultimately, in the presence of predators, lizards do not cease their use of risky signals altogether, but instead decrease their risk through more subtle shifts in signaling behavior. (Communication 2, Wednesday 2:30 PM - 2:45 PM, NMM1)

276 Early life and corticosterone: a study of stress and independence in the Northern Mockingbird (Mimus polyglottos).

Christopher G. Sims*

University of Mississippi (Csims@olemiss.edu)

It has long been known that hormones aid birds in avoiding stressful perturbations. The hormone of stress in birds is corticosterone. In this study I asked the question, is the stress response present or even necessary in young birds that are still dependent on parental care? In the summer of 1998 and 1999 blood samples were taken from seven age classes of Northern Mockingbirds to measure the corticosterone stress response. Young birds (nestlings) were found to have a significantly reduced stress response when compared to independent juveniles and adults. This response increased in magnitude as birds gained independence from the parents. Subsequent experimentation showed that nestlings lacking a stress response were not producing the necessary precursors that stimulate corticosterone secretion, thereby suggesting that some level of development was absent in these young birds. Increases in baseline corticosterone concentrations from 6 days post hatch until the individuals fledged from the nest suggests a role for this hormone in facilitating energetic demands involved with this behavior of independence. (W.C. Allee Competition, Monday 2:45 PM - 3:00 PM, Sale)

277 Responses of great gerbils to alarm vocalizations

Colin D. Smith*, Jan A. Randall, Konstantin A. Rogovin, & Kelly C. Collins

San Francisco State University (cds@sfsu.edu)

Great gerbils Rhombomys opimus of central Asian deserts exhibit alarm behavior that parallels both ground squirrel vocalizations and kangaroo rat footdrumming. In order to explore what information is conveyed by alarm calls, we tested the hypotheses that responses to alarm calls change depending on stimulus (different predators) and differ based on caller and respondent age and sex. We observed responses to a monitor lizard Varanus griseus or a domestic dog in ten minute tests, in ten family groups. It appeared that the different response patterns did not depend on the predator, although there were more alert postures in the lizard tests. 55% of the 151 alarm calls were issued with no other gerbils visible. 48% of the animals present to respond did not, while 35% responded by assuming a frozen alert posture. More than the alarm call may be required to understand what is being conveyed. We will further analyze layers within the experimental data, as well as responses to over one thousand calls studied during baseline observations. (Regular Poster Session, Tuesday evening, Gym)

279 Social communication about adulterated food in Cotton-top Tamarins

Charles T. Snowdon* & Carla Y. Boe

University of Wisconsin (snowdon@facstaff.wisc.edu)

Cotton-top tamarins are cooperatively breeding monkeys where fathers and non-reproductive helpers carry infants and share food with infants at the time of weaning. The high degree of cooperative behavior suggested a possible social transmission about food quality. We presented 10 family groups with a highly preferred food (tuna fish) adulterated invisibly with white pepper. An equally preferred food that was not adulterated was presented as a control. Both foods were presented weekly for three weeks and subsequently the tuna was presented weekly without pepper. In groups only 25% of animals ever sampled the adulterated tuna, the others avoiding even tasting tuna. Once an animal sampled the peppered tuna it rarely sampled it on subsequent weeks. Some groups stopped eating tuna for more than 15 weeks after normal tuna was restored. Tamarins greatly reduced food sharing of peppered tuna with infants. Visual signals of disgust were the primary means of communication. Social communication about unpalatable food allowed other group members to avoid even sampling the food. Social communication may be particularly effective in cooperatively-breeding species. Supported by USPHS Grant MH 29775. (Communication 1, Wednesday 11:15 AM - 11:30 AM, NMM1)

282 Effects of habitat features and disturbance on abandonment of breeding areas by South American fur seals

Monica A. Sommer*, Daryl J. Boness & Stephen J. Insley

University of New Hampshire & Smithsonian National Zoo (msommer@hopper.unh.edu)

Over several decades South American fur seal (Arctocephalus australis) populations at Punta San Juan, Peru have declined dramatically and seals have abandoned some breeding sites. Little research has investigated what factors might influence abandonment of sites. We examined how habitat features and disturbance (humans and sea lions) affected whether areas were currently used (n=6), abandoned (n=5), or apparently not used in the past (never; n=6). Binary recursive partitioning analysis revealed that presence of shade classified areas as 'currently used' vs. 'formerly or never used' (correctly classified 100% and 73% of cases respectfully). Discriminant analysis correctly classified 100% of cases. Abandoned areas were more likely to be disturbed by humans and sea lions, and had greater slopes at the landward side than currently used areas. Areas never used were more likely to have sand or gravel shores, no sea spray and no disturbance by sea lions. A. australis apparently consider thermoregulatory needs and the potential for sea lion disturbance in selecting and maintaining breeding areas. Habitat features associated with thermoregulation may be more important to fur seals in Peru, which breed at lower latitudes and are at greater risk of overheating on land, than other populations in South America. (Habitat Choice, Monday 5:30 PM - 5:45 PM, Sale)

284 Communal versus selfish caching among gray squirrels (Sciurus carolinensis)

Mark D. Spritzer*

Miami University (spritzmd@muohio.edu)

Many animals store food so that they can consume it at a later time, but some species share stored food with relatives. I studied whether gray squirrels were selfish with the nuts that they buried or if they shared them with relatives. I predicted that if squirrels share food with relatives, then related squirrels should bury nuts near one another. In contrast, if squirrels behave selfishly, they should clump their food in a centralized location to make it more defensible. This study was conducted with 140 squirrels on the University of Florida campus. DNA was taken from blood samples, which allowed me to determine how related all the squirrels were to one another. I gave the squirrels piles of pecans and observed the direction in which they carried nuts. I also gave some squirrels pecans wrapped with aluminum foil so that I could use a metal detector to locate buried nuts. The relatedness of neighboring squirrels did not influence the location or direction in which nuts were stored. Squirrels clumped their own nuts near one another and moved nuts toward centralized locations. These results suggest that gray squirrels store food for selfish reasons rather than sharing it with relatives. (Social Behavior 1, Monday 3:45 PM - 4:00 PM, NMM2)

285 House wren nest defense behavior: do sex and male breeding strategy affect defense levels?

Thomas McK. Sproat*

Ball State University (00tmsproat@bsu.edu)

Defending eggs and young against potential predators can be important for birds caring for young. This study looked at which parent was more active in defending their young against predators and if this changed when the male tried to acquire another mate. Experiments presented stuffed eastern bluebird, brown-headed cowbird, and house wren models to house wren nests. The levels of "active" and "passive" defense behaviors and wren vocalizations were recorded for each parent. Results showed that males took a greater role than females in defense against the house wren model. However, females showed slightly more "passive" defense behaviors than males against the bluebird. Males who remained attentive to their nest and young showed more "active" behaviors toward the house wren and cowbird, than males attempting to find another mate. Females showed no differences in defense levels based on their mate's breeding strategy. Male house wrens may exhibit greater defense levels as part of their territory defense role. Female house wrens may show lower defense levels, and use more "passive" behaviors, as a result of potentially greater risk to her safety. Males not attentive to their initial nest appear to sacrifice defense of existing young for opportunities to find another mate. (Parental Care 1, Sunday 11:30 AM - 11:45 AM, NMM1)

287 Eastern bluebirds incur ectoparasitism in order to minimize predation

Mark T. Stanback*, David Lamar, Julie Martin, Suzanne Moore, Meg Seifert, Ambrose Tuscano & Annie Welsh

Davidson College (mastanback@davidson.edu)

By nesting in cavities low to the ground, secondary cavity nesters increase the likelihood of detection by mammalian and reptilian predators. By reusing soiled nests, such birds incur the costs of nest ectoparasites. By experimentally varying these two factors, we tested the relative importance of each to nest site fidelity in Eastern Bluebirds. Choice experiments demonstrated that bluebirds avoid reusing soiled boxes (if also given a clean box) but prefer to reuse successful nest boxes (if they are clean). Bluebirds also showed a significant preference for high (5 ft) vs. low (4 ft) boxes for their first nests of the year, suggesting sensitivity to predation risk. For second nests, we forced bluebirds to choose between their successful soiled high box and a clean low box. Bluebirds reused soiled high boxes significantly more often than they used clean low boxes and significantly more often than they reused soiled cavities when given boxes of equal height. Thus under these conditions, bluebirds are willing to incur the costs of parasitism in order to lessen susceptibility to predators. (Habitat Choice, Monday 4:00 PM - 4:15 PM, Sale)

288 Repeatability of extra-pair mate choice in female Tree Swallows

Mary K. Stapleton*

University of Wisconsin - Milwaukee (mstap@csd.uwm.edu)

The ability to genetically determine paternity of birds has dramatically affected the study of avian mating systems in the past 10 years. Paternity analyses have shown that many bird species in which pairs were thought to be strictly faithful are actually promiscuous. One of the most intriguing questions regarding mating outside the pair bond (extra-pair mating) is how females benefit by having their clutch fathered by multiple males. Many studies of mate choice suggest that females are choosing males for their superior genes. If this is the case, females are expected to be consistent in their choice of males. Tree Swallows exhibit some of the highest levels of extra-pair mating among North American birds. I tested whether female Tree Swallows are consistent in choosing within-pair and extra-pair males within a single breeding season by experimentally forcing females to lay a second clutch and, thus, choose to remate with the same or different males. Fathers of young in the first and replacement broods were identified using parentage analysis based on DNA. We discuss our results in relation to the assumption that female birds consistently choose males to improve the genetic quality of their offspring. (Mate Choice 4, Wednesday 9:30 AM - 9:45 AM, NMM2)

290 The effects of nest mites on the reproductive biology of the house finch

Andrew M. Stoehr*, Paul M. Nolan, Geoffrey E. Hill, & Kevin J. McGraw

University of California, Auburn University & Cornell University (amstoehr@citrus.ucr.edu)

Parasites may have many influences on the biology of their hosts. One theory suggests that female birds use the bright colors of male birds as cues of resistance to parasites or other measures of quality when choosing with whom to mate. Male house finches vary in color from bright red to orange or yellow, and females prefer to mate with red males. This may be because these males are more resistant to parasites or make better fathers. However, our research suggests this is not true and that other factors must explain why females prefer red males because nestlings in the nests of red males do not have fewer nest mites and adult house finches do not alter their levels of parental care if their nestlings have many parasites. However, they may avoid these parasites by nesting early in the spring. (Immune Systems & Behavior, Wednesday 2:15 PM - 2:30 PM, NMM2)

292 Discrimination of foraging paths produced by different search models

Richard E. Strauss, Chris L. Higgins* & Ozlen Konu

Texas Tech University & University of Tennessee (chiggins@ttacs.ttu.edu)

The way an organism "thinks" about how it can consume available food plays a key role in the maximum intake of food for that organism. In other words, the ways in which an animal forages for food determines the net amount of energy it can consume. To represent the behavior of an organism as it forages, we developed a set of computer programs that simulate the searching behavior of an imaginary organism feeding according to each of nine different behavioral models. We characterized the different models by the lengths and shapes of the resulting search paths. If we then observe the search of an actual predator, we should be able to classify its behavior into one of the nine models. Based on the characteristics of the search paths produced by the simulations, we were only partially able to distinguish among the models. However, the results give us confidence that we may ultimately understand the rules that different predators follow by classifying the results of their foraging behaviors, which in turn should give us insight into how an animal "thinks." Future work will involve varying the simulations to be more realistic and to include more and different kinds of tactics. (Foraging, Tuesday 2:15 PM - 2:30 PM, NMM2)

293 Does extra-pair paternity correlate with actual fertilization success?

Bridget J. M. Stutchbury*, Ryan Norris, Trevor E. Pitcher, Rusty Gonsar & Elaina M Tuttle

York University & St. Mary's College of Maryland (BStutch@yorku.ca)

Most songbirds that have been studied thus far are not monogamous, despite the fact that a single male and female live together on a territory and raise young together. In hooded warblers, both males and females sneak next door to obtain copulations with neighbors. In this study we used radiotelemetry to determine who visited whom, and how often. Males varied greatly in the frequency and duration of 'extra-territory forays'. Males occupying territories in isolated forest fragments nevertheless left their 'islands' of forest to travel to nearby fragments. We used DNA fingerprinting to determine what aspects of male foray behavior determine success or failure in achieving actual fertilizations with neighboring females. (Mating & Reproductive Success, Monday 3:45 PM - 4:00 PM, NMM1)

295 Mate Choice and Male-male Competition in Common Freshwater Gobies

Ho Young Suk* & Jae Chun Choe

Seoul National University (rhodeus@hotmail.com)

The question of how animals choose their mates has long been of interest to behavioral ecologists. Previous studies of fish with paternal care have demonstrated the importance of male body size and nest site characteristics. Here we show results from experiments carried out on a freshwater fish, Rhinogobius brunneus which exhibits paternal care. Our findings show that, in contrast to the common view, females based their mate choice decision on the length of the first dorsal fin (FDF) of males, but mated randomly with respect to male body size and nest size. Males with longer FDFs had no advantage in inter-male competition. An interesting question remains, however: what benefits should accrue to females when choosing her mates with longer FDF? (Mate Choice 2, Sunday 1:45 PM - 2:00 PM, NMM2)

296 Dispersal in Yellow-eyed Juncos

Kimberly Sullivan*

Utah State University (yejunco@cc.usu.edu)

Although female birds typically move farther between nesting seasons and from the nest they hatched in to a breeding territory than males, this is not the case in Yellow-eyed Juncos breeding in Arizona. Both male and female Yellow-eyed Juncos show site fidelity with birds returning to nest each year in the same area and breeding near the nest where they hatched. Yellow-eyed Juncos appear to locate a breeding territory during their first summer soon after they leave their parents. They then return to that area year after year. (Dispersal, Sunday 5:15 PM - 5:30 PM, Sale)

297 Environmental Enrichment for Giant Pandas

Ronald R. Swaisgood*

Zoological Society of San Diego (rswaisgood@sandiegozoo.org)

Environmental enrichment can be a valuable tool for promoting the health and well-being of captive animals. We tested an enrichment program for giant pandas at the Wolong Breeding Center in China and found that pandas spent significantly more time active and Displayed a greater variety of positive behaviors when enrichment was present. There was also a significant reduction in stereotypic behavior (such as pacing) and food-anticipation behaviors. We saw this effect even when pandas were not directly interacting with the enrichment materials, suggesting that enrichment had a carry-over effect to their daily lives. Opportunities to perform more natural behavior appeared to improve their well-being, though the actual response to enrichment varied with the animal’s age. All five enrichment items proved equivalent in their ability to increase or reduce behavioral measures relating to well-being, but each item promoted a distinct behavioral profile consistent with specific attributes of the enrichment item. (Conservation, Wednesday 9:30 AM - 9:45 AM, Sale)

299 Female Drosophila melanogaster prefer more energetic pulse song. Sometimes.

Becky Talyn*

University of Maine (becky.talyn@umit.maine.edu)

Animal males often produce elaborate Displaysthat include color patterns, calls or songs, and chemical pheromones. These signals can attract females, or encourage nearby females to choose them as mates. We studied the functions of two courtship signals from the fruit fly Drosophila melanogaster, pulse song and sine song. Artificial songs were generated and played to groups of males and females. These songs were similar to natural songs, but allowed us to change individual characteristics to explore their functions. We discovered that females prefer songs containing a high amount of pulse song, probably because males who produce these types of song are genetically superior to other males. Females who mate with these males will produce better offspring. To our surprise, however, females did not prefer songs that contained a high amount of sine song. Since sine song production requires a male to exert energy, it is perplexing that they would produce this signal in the absence of female preference. We suggest that sine song must occur as a byproduct of an other courtship signal or behavior. (W.C. Allee Competition, Monday 3:00 PM - 3:15 PM, Sale)

303 The process of vocal imitation

Ofer Tchernichovski*, Partha Mitra, Thierry Lints & Fernando Nottebohm

Rockefeller University Field Research Center (tcherno@rockvax.rockefeller.edu)

It has been often suggested that the mechanisms of vocal imitation in songbirds and humans are similar, yet, no one in the past has subjected the ontogeny of learned sounds to quantitative, close scrutiny. Two theories have taken root. One argues are that all infants – and young songbirds – have at their disposal a system of universal sounds, from which subsets typical of each language or dialect are chosen. The other one argues that imitation emerges from an amorphous matrix by the gradual modification of preexisting sounds, which is achieved by a process of gradual error reduction. The latter process would require that the pupil act upon error signals and work to minimize them. Our study of vocal learning in zebra finches suggests that the process of imitation is more complex and involves the production of prototype sounds that are induced by the model but initially do not offer an obvious match to the song model. These prototype sounds undergo transformations that cannot be explained just as error reduction steps. Instead, we propose a generative process that follows pre-ordained rules and provides the material for error correction. (Learning of Social Signals, Sunday 4:30 PM - 4:45 PM, NMM1)

304 Combining sensory modalities in a communicative Display: A field study of visual and chemical signals

Julie Tolman Thompson & Emilia P Martins*

University of Oregon (emartins@work.uoregon.edu)

Animal communication often contains multiple types of signals. For example, a person might say "hello" (an acoustic signal) and wave (a visual signal) simultaneously. Previous research shows that South American Liolaemus lizard species differ in the relative number of visual and chemical signals used, and that there may be an evolutionary trade-off between the use of visual and chemical cues. In this study, we focused on two species that were expected to be different in their use of chemical and visual signals. Detailed field observations confirmed our predictions. The species that used visual Displaysfrequently was less likely also to use chemical Displays, whereas the species that used mostly chemical signals did not also produce frequent visual signals. These results confirm the suggestion that there may be a trade-off between the use of different sensory modalities in communication. (Evolution of Signals, Tuesday 10:15 AM - 10:30 AM, NMM1)

305 Social interactions and time budgets of Icelandic mares at the time of foaling

Anna G. Thórhallsdóttir*, Hrefna Sigurjónsdóttir & Machteld van Dierendonck

Agricultural University & Icelandic University of Education (annagth@cc.usu.edu)

The Icelandic horse is a special breed that has evolved in total isolation from other breeds for more than thousand years. Numbering close to a 100,000 in Iceland, the horses are for the most part semi-wild and very little research has been conducted on their social behavior. We observed a group of 34 horses for 655 hrs, 24 hrs a day during foaling time in spring. The aim of the study was to record interaction patterns between different horse groups (age and sex), and the introduction of a new foal into the group. Dominance rank was positively correlated with age. Animals preferred to allogroom and play with partners of the same sex-age group, and the mares with mares the same 'state'. Older mares and fillies played less than colts. Interestingly, kinship was found to have a positive effect on interactions within the group. Mares were seen to actively protect other mares with newborn foals. Mares spent about one fourth of their time resting and two thirds of their time eating. Mares spent more time standing and resting the first week after the birth of their foal. Stallion like behavior of both pregnant and barren mares was observed. (Regular Poster Session, Tuesday evening, Gym)

306 Olfactory Communication of Free-Ranging North American River Otters Lontra canadensis

Deborah Boege Tobin* & Godfrey R. Bourne

University of Missouri - St. Louis (s982004@admiral.umsl.edu)

Field research exploring the functions and mechanisms of chemical communication for large mammalian species is quite sparse. Our on-going study marks the first systematic investigation of olfactory communication in free-ranging North American river otters, Lontra canadensis. By implementing live trapping and radio tracking methodology (via abdominal intraperitoneally implanted radio transmitters), home range, core area use, and association indices will be determined for 45-60 river otters from 3 sites throughout the state of Missouri. Using a habituation-discrimination paradigm and two-way preference testing, we will attempt to determine whether river otters can discriminate between scents from different individuals (e.g., familiar vs. stranger, male vs. female) on the basis of chemical cues. In addition, microhabitat assessments will be made for all radio fix and successful trapping locations. Using GIS tools, these assessments will allow determination of habitat-use indices that can subsequently be applied at a much larger scale throughout much of this species range. These results will have implications that can be applied to the conservation and management of this species. Preliminary results are presented here. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

308 Linking dispersal and marriage in humans: life history data from Oakham, Massachusetts, USA (1770-1870)

Mary C. Towner*

NCEAS (towner@nceas.ucsb.edu)

Dispersal, individual movement from one location to another, is a highly variable behavior. For most primates, biological anthropologists emphasize inbreeding avoidance and intrasexual competition for mates in explaining dispersal, and the main hypothesis for sex-biased dispersal links dispersal to mating systems. For humans, behavioral ecologists place greater emphasis on resource competition in explaining dispersal, and a large gap exists between what is known about dispersal and what is known about mating. I examine the link between dispersal and marriage using life history data for people from the small farming town of Oakham, Massachusetts (1750-1850). I find that dispersal status, timing, and destination were interconnected with marital status, timing, and spouse's place of origin. Men, unmarried individuals, and individuals with spouses from Oakham were less likely to disperse than their counterparts. Individuals with spouses from Oakham also married earlier than others. dispersal infrequently preceded marriage, but instead was evenly split between coinciding with or following some time after marriage. Dispersal more often coincided with marriage for women, who were also more likely to disperse to their spouses town of origin than were men. An interpretation of these findings suggests little support for inbreeding avoidance, but rather a combination of access to mates and resources, as explanations for the variation found in Dispersal from Oakham. (Dispersal, Sunday 5:30 PM - 5:45 PM, Sale)

311 Natural Concept Formation in Captive Orangutans (Pongo pygmaeus) Using a Touch Screen

Jennifer Vonk* & Suzanne E. MacDonald

Atkinson College (jvonk@yorku.ca)

Pigeons and several species of non-human primates have demonstrated learning for abstract natural concepts such as "tree", "water", and "human". Pictures of various exemplars of the categories are typically shown by slide and the subjects are required to press a key in response to instances of the correct category. The current study utilizes a touch screen to present photographs to six zoo-housed orangutans ranging in age from 2 to 41 years. The orangutans are required to touch the photo of the correct exemplar in order to obtain a food reward. Each subject is presented ten pairs of photos within each trial and receives only one trial per day. Each pair of photos represents a choice between two distinct categories such as orangutan versus human or orangutan versus "other primates". The photos are presented in random order with the pairings also being randomized. When the subjects reach consistent performance of at least 80% correct first choices they are given transfer trials which consist of all new photographs (exemplars) of the same concepts. One adult male consistently performs with above 80% accuracy on concept tests that vary according to the level of abstraction required. However his performance on earlier trials may have been partially mediated by the use of colour as a cue. (John Paul Scott's Founders Poster Session, Tuesday evening, Gym)

312 Assortative mating by ornamentation in Northern Cardinals

Bryan P. Wallace*, Jodie Jawor & Randall Breitwisch

University of Dayton (octobre2@hotmail.com)

Assortative mating in animals based on aspects of body size is well established. There is less evidence for assortative mating based on ornamentation in species wherein both sexes are ornamented. We measured the expression of visual ornaments of Northern Cardinals (Cardinalis cardinalis): bright red upper breast plumage in males and bright red underwing coverts of females. A sample collected over a five-year period revealed that this population mates assortatively based on these ornaments. Previous research in another population showed that brighter male cardinals defended better territories and were mated to females that nested earlier in the season than the mates of duller males. Previous research in this population showed that brighter female cardinals provisioned their nestlings at higher rates than did duller females. Together, these findings suggest that high quality male and female cardinals mate with one another. (Regular Poster Session, Tuesday evening, Gym)

313 Sweetness-based object retrieval by Norway rats related to consummatory effort and deprivation Richard J. Wallace* University of New Hampshire (rjw@cs.unh.edu)

These experiments examined object retrieval by Norway rats based on sweetness, to better understand its relation to food hoarding. Rats retrieved either of two types of object placed in quantity at the end of an alley placed before the home cage for a short daily period. In Experiment 1 the effect of handling effort on the decision to consume vs. retrieve another object was tested by encasing the sweet object in a gelatin capsule. This was paired with a similar unsweetened object. Experiments 2 and 3 used sweet object/food pellet and sweet/non- or less-sweet pairings under adlib and deprivation conditions. Results were, (i) when handling was made difficult, retrieval of sweet objects was often followed by further retrieval rather than immediate consumption, (ii) under adlib feeding rats retrieved sweet objects in preference to food pellets; this preference was maintained under mild deprivation, but at _ 90% predeprivation weight rats switched to a food pellet preference. Therefore, (i) sweetness can support object accumulation ("hoarding"), (ii) increased value of other foodstuff in relation to sweetness during deprivation, observed for feeding, also occurs for retrieval, (iii) the consume vs. retrieve decision holds across object properties that induce retrieval and underlies accumulation. (Foraging, Tuesday 2:00 PM - 2:15 PM, NMM2)

315 Reactive distances: their utility in applied ethology

George H. Waring*

Southern Illinois University (waring@siu.edu)

Animal reactivity at specific distances has long been noted (e.g., Hediger, 1950, Wild Animals in Captivity). Terms such as flight distance and aggressive distance have been used by authors to identify two of these traits. For example, an animal will take flight only when an intruder has encroached to a certain distance. And when flight is not an option, the uneasy animal may become aggressive and defend itself against the intruder when the distance narrows to a specific point. Different behavioral situations have their own specific reactive distance, such as, alert distance, withdrawal distance, approach distance, strike distance, attack distance, submissive distance, individual distance, and maximum social distance. This paper will clarify and highlight examples. Each of these spatial phenomena remains consistent under like circumstances. Thus these distances can be highly relevant when herding, confining, or otherwise manipulating animals. Stress can be reduced and safety enhanced. But distances can alter as circumstances vary. It is noteworthy that changes in the spatial elationships over time can help assess the health, development, adaptation, and well-being of individual animals from afar. (Applied Animal Behavior, Tuesday 2:30 PM - 2:45 PM, Sale)

316 What is good about good genes in gray tree frogs: How is call duration linked with larval quality?

Allison Welch*

University of Missouri - Columbia (welcha@missouri.edu)

Male Displaystraits are predictive of offspring quality in some species, although the basis for the relationship between Display traits and offspring quality is not well understood. Female gray tree frogs (Hyla versicolor) prefer males with long calls, and offspring of males with long calls have been shown to be of higher larval quality than offspring of males with short calls. I tested whether variation in tadpole activity and metabolism contributed to an effect of call duration on larval quality. Under low food conditions, offspring of long-callers were larger at metamorphosis than offspring of short-callers, but had similar larval periods; offspring of long- and short-callers did not differ in larval period or mass at metamorphosis under high food conditions. Additionally, tadpoles that spent more time feeding tended to have higher ingestion rates, and tadpoles with higher ingestion rates tended to have shorter larval periods. However, neither time spent feeding, nor ingestion rate, nor digestive efficiency affected mass at metamorphosis. Thus, the difference in mass at metamorphosis between offspring of long- and short-callers in this experiment was not attributable to variation in activity or metabolism. (W.C. Allee Competition, Monday 3:15 PM - 3:30 PM, Sale)

317 Influence of variation in social experience on development of courtship and communication in cowbirds, Molothrus ater

David White*

Indiana University (dajwhite@indiana.edu)

In a diversity of species, individuals depend on interactions with others to learn a vast amount of their behavioural repertoire. The impact of the social environment on development of mating behaviour was investigated in cowbirds. Using naturally occurring variation in social experience, distinct social environments were created in aviaries for male and female cowbirds. Juvenile and adult females were housed in one of four conditions differing only in the age classes of males present. Groups of juvenile and adult females were housed with: (1) juvenile and adult males, (2) only juvenile males, (3) only adult males, or (4) no males. Across the four conditions, dramatically different cultures emerged from the differences in social composition. Males across conditions differed in: amount, quality, and type of song produced as well as the ways in which they used their song. Furthermore, both males and females differed across conditions in how they assorted spatially. Results are consistent with the hypothesis that the social environment can impact the developmental trajectory of mating behaviour. (Learning of Social Signals, Sunday 4:00 PM - 4:15 PM, NMM1)

318 Primate Conservation and Behavior: A Field Course in Barbados

Brent Clark White*

Centre College (bcwhite@centre.edu)

Fifteen years ago a conservation program was established for the Barbados green monkey (Cercopithecus aethiops sabaeus). The features of this program illustrate many of the problems and controversial issues associated with conservation biology, including sustainable harvesting of a primate and conservation of an exotic species. These topics and the opportunity for close observation of wild vervets, make Barbados an ideal site for an undergraduate field course. The present paper describes a course that was completed in January of 1999. The class conservation project involved a survey of visitors and residents which was designed to contribute to a prior economic analysis of the conservation program. The results suggest an untapped potential for the monkeys to contribute to tourism. We also found mixed attitudes of Barbadians toward the monkeys which may have an important influence on the conservation program. (Regular Poster Session, Tuesday evening, Gym)

320 Winter foraging behavior of Yellow-bellied Sapsuckers in Central Mississippi.

H. Dawn Wilkins*

Mississippi State University (Hdw3@ra.msstate.edu)

Few vertebrates wound trees to forage on the resulting sap flow. The factors used to choose certain trees and avoid others are known only anecdotally. Most information on the winter behavior and ecology of Yellow-bellied Sapsuckers (Sphyrapicus varius) is limited to observations where they would not normally be during the winter. Observations began once a sapsucker was spotted and included the bird's behavior, sex, age, height and position in the tree, tree species, and whether the substrate was living or dead. Females were rarely observed and adults were more common than juveniles. Sapsuckers spent about 50% of the time excavating and maintaining sapwells. They preferred Hickory trees (Carya spp.) and tended to excavate wells on trees with a high percentage of the trunk covered with branches. These trees may have higher sugar concentrations because of increased photosynthetic area associated with a larger crown. Juvenile sapsuckers used parts of the trees differently than adults and also foraged at different heights. Such differences in the vertical distribution of foraging may help alleviate intraspecific competition based on age. (Regular Poster Session, Tuesday evening, Gym)

322 Effects of competition between ants and burying beetles

Charmaine Woodard* & Diane M. Post

University of Texas - Permian Basin (cwotter@aol.com)

Burying beetles hide small vertebrate carcasses underground and process them for consumption by their young. These beetles are rare among invertebrates because they provide prolonged care of the young. They encounter competition for carcasses from sources such as conspecifics, ants and carcass decomposition. It is surmised there may not be many burying beetles in arid regions because of increased competition. Our research looked at the effect of competition with omnivorous ants Solenopsis spp. on burying beetles Nicrophorus marginatus reproductive success. Both were trapped in arid west Texas. We assessed the time to bury the carcass and number of larvae produced. Control trials were run with pairs of beetles and a mouse. Experimental trials were conducted with pairs of beetles, a mouse and ants. Initial results indicate that there is no difference in number of larvae produced, or time required to bury the carcass when ants were present or absent. Preliminary results suggest that a factor other than competition with ants may limit burying beetle reproductive success in arid environments. (Regular Poster Session, Tuesday evening, Gym)

323 Responses of Meadow Voles (Microtus pennsylvanicus) and Prairie Voles (M. ochrogaster) to over-marks from opposite- and same-sex conspecifics

Raymond L Woodward, Jr*, Kim Bartos & Michael H. Ferkin

University of Memphis (woodward@memphis.edu)

Over-marking occurs when one individual deposits its scent mark on the scent mark of a conspecific. Previous studies examined how meadow and prairie voles exposed to an over-mark later respond to top- and bottom-scent marks. Both species responded similarly to the top-scent but differently to the bottom-scent mark. This study examines their response to same-sex and mixed-sex over-marks to determine whether these responses reflect the different tactics individuals in non-monogamous (meadow voles) and monogamous (prairie voles) species use to attract mates and compete with rivals. In experiment 1 where donors and subjects were of the same sex, all subjects spent more time investigating the odor of the top-scent donor than the bottom-scent donor. In experiments 2 and 3, meadow voles exposed to a mixed-sex over-mark spent more time investigating the odor of the opposite-sex donor independent of its position in the over-mark. In contrast, in the same two experiments prairie voles spent more time investigating the opposite-sex donor if it was the top-scent donor. The data support the following speculations. First, over-marking serves a competitive function. Second, for a non-monogamous species the scent marks may be directed towards attracting multiple mates. Third, in a monogamous species, the scent marks may be directed towards establishing and maintaining a pair bond. (Mate Choice 3, Monday 2:30 PM - 2:45 PM, NMM1)

324 Burrows as an important resource influencing the mating system of mantis shrimps

Jen L Wortham*

University of Louisiana - Lafayette (jlw6433@louisiana.edu)

The question of how territorial behavior influences the mating systems of animals has been a problem to evolutionary biologists. Possession of a territory as well as territory quality may influence decisions and behaviors that individuals make regarding mating. In many animals, territories are necessary resources for mating, brooding eggs, feeding, and refuge from predators. Thus, in these species, males may fight amongst themselves for the "best" territories, as these high quality territories may be more attractive to females that need the burrows to successfully reproduce. I study marine crustaceans known as mantis shrimp to find out how mating behaviors in these animals are related to territoriality. Mantis shrimp live in burrows which are usually defended against all other individuals of the same species. My research reveals that preferred burrow size is related to body size and males may behave differently regarding territory ownership. Individuals are more likely to live in a burrow with an individual of the same sex than the opposite sex. My results indicate that the burrow is an equally important resource for both sexes. (Dominance & Resource Defense, Tuesday 11:00 AM - 11:15 AM, NMM2)

326 The importance of competition, female choice, and size in the mating behavior of a montane leaf beetle

Kasey M. Yturralde*

Sonoma State University & White Mountain Research Station (beetle_lady@yahoo.com)

Male-male competition, female mate choice, or both may drive the evolution by sexual selection on male insects. I studied the relationship between mating success in the field and in the laboratory for the montane leaf beetle, Chrysomela aeneicollis. My study design allowed me to determine the relative roles of competition and mate choice and to correlate size and fluctuating asymmetry with mating success. I separated mate choice from competition effects by conducting two-choice tests with tethered and untethered males. Males found mating in the field mated significantly more compared with single males in nature. Male mating success in the laboratory and the field was not correlated with male size. On the other hand, female size was strongly positively correlated to mating success and I found evidence for size assortative mating. Chrysomela aeneicollis exhibits true fluctuating asymmetry, yet none of the FA indexes were related to mating success. In conclusion, field status can be used as an indicator of male mating success in C. aeneicollis. There was evidence that female choice influences male mating success. Female mating success was positively correlated with female size, which was positively correlated with the size of her mate. (Mate Choice 2, Sunday 2:30 PM - 2:45 PM, NMM2)

328 Physiological correlates of energy regulation patterns in fox squirrels

Denise L. Zielinski*, Kevin McCurdy & Jeffrey R. Lucas

Wabash College (zielinsd@wabash.edu)

Fox squirrels store energy as fat and cached food, however little is known about the physiological conditions accompanying the utilization of these alternative energy storage forms. We exposed adult males to different patterns of food access in the laboratory throughout the year to characterize seasonal patterns in body mass regulation and caching behavior in response to different energetic conditions. We also monitored plasma glucose, triglyceride, leptin (a hormone produced by fat cells), and testosterone levels. Body masses peaked in the spring and increased after the squirrels experienced food deprivation. Glucose and triglycerides decreased with body mass, but only during summer and fall. Body mass increased with leptin and decreased with testosterone. Caching rates increased after food deprivation, but did not vary seasonally. Caching rates also decreased with triglyceride, glucose and testosterone levels. These results begin to illuminate the proximate factors involved in squirrels' complicated energetic repertoire. (Mating Behavior, Monday 11:45 AM - 12:00 PM, NMM1)

329 Social environment and immunity in male red jungle fowl

Marlene Zuk* & Torgeir S. Johnsen

University of California - Riverside (mzuk@citrus.ucr.edu)

The social environment has a profound effect on many aspects of an animal's biology. We examined the relationship between social dominance, immune response, and ornamentation in captive red jungle fowl by comparing these variables in males housed individually with a single female to those in the same males after they were placed in flocks with a male and three females. Males with larger combs before being placed in the flocks were more likely to become dominant, in accordance with earlier work showing that comb size is important in social interactions. Dominant males' combs grew after flock formation while subordinate males' combs shrank. Immune response was stronger in males that later became dominant, both before and after flock formation, although the difference between dominant and subordinate birds was more pronounced after multi-male groups were formed. Males of different quality thus pay different costs to maintain ornamentation and immune defense. Variation in these individual-level responses to similar challenges has important implications for the way in which natural selection acts on life history. (Immune Systems & Behavior, Wednesday 1:45 PM - 2:00 PM, NMM2)