Animal camouflage: compromise or specialize in a 2 patch-type environment?

Many animals possess camouflage markings that reduce the risk of detection by visually hunting predators. A key aspect of camouflage involves mimicking the background against which the animal is viewed. However, most animals experience a wide variety of backgrounds and cannot change their external appearance to match each selectively. We investigate whether such animals should adopt camouflage specialized with respect to one background or adopt a compromise between the attributes of multiple backgrounds. We do this using a model consisting of predators that hunt prey in patches of 2 different types, where prey adopt the camouflage that minimizes individual risk of predation. We show that the optimal strategy of the prey is affected by a number of factors, including the relative frequencies of the patch types, the travel time of predators between patches, the mean prey number in each patch type, and the trade-off function between the levels of crypsis in the patch types. We find evidence that both specialist and compromise strategies of prey camouflage are favored under different model parameters, indicating that optimal concealment may not be as straightforward as previously thought. Copyright 2007, Oxford University Press.