Learning profitable habitat types by juvenile crayfish.

Habitat selection is fundamentally important to animal ecology, and animals that can learn about habitats can increase the probability of avoiding detection by predators or quickly finding food. Here, we tested whether juveniles of the red swamp crayfish, Procambarus clarkii, can learn preference for habitat types based on experience with food availability. Crayfish were housed in arenas with two habitat types, half leaf habitat and half rock habitat. Over several days, crayfish were fed consistently in one of the habitat types. Initial tests revealed that crayfish had an innate preference for the leaf habitat, but conditioning over 2-3 weeks was sufficient to shift this preference to the rock habitat based on habitat cues rather than other spatial cues in their environment. The ability to learn the relevance of habitat features may be an important trait for the colonization success, and subsequent impact, of introduced species.