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A number of group foragers are known to engage in a producer-scrounger (PS) foraging game in which only individuals in the producer strategy search for food, the scroungers wait for opportunities to join. Prey exploited by predators engaged in a PS game could gain by adopting predator evasion tactics that shift the PS equilibrium of their predators towards a larger number of non-searching scroungers. Prey can achieve this by imposing foraging costs that are specific to predators engaged in the producer strategy. In this study we ask whether prey cryspsis, a tactic that is demonstrably efficient against solitary predators, imposes a producer-specific cost to group foragers that shifts PS equilibria towards more scrounging. We exposed four flocks of six nutmeg mannikins (Lonchura punctulata), small granivorous passerines that have repeatedly been documented to play PS foraging games, to clumps of white millet seeds placed against on one of two backgrounds that either made them cryptic or conspicuous. We found that foraging under cryptic conditions required more time to find food, resulted in a greater frequency of detection errors, had no effect on vigilance but significantly increased the frequency of scroungers at equilibrium in three of four flocks. Having socially foraging predators may provide prey with an extra incentive to evolve producer-specific costs such as cryptic coloration.