Antipredator mechanisms of Australian frogs

We examined the antipredator mechanisms of 19 Australian hylid species (two genera) and 23 myobatrachid species (nine genera). Frogs of 39 of the 42 s pecies exhibited one or more defensive mechanisms (other than escape), incl uding postures, bright coloration, adhesive skin secretions, and/or calls. Defensive posturing occurred in individuals of 38 species, and varied in re lationship to morphology and localization of skin glands. Bright colors, wh en present, typically were displayed during defensive postures. We document ed dramatic geographic variation in the antipredator display of cane specie s, Limnodynastes tasmaniensis. Defensive postures were accompanied by secre tions from dorsal skin glands. These secretions were sometimes associated w ith a distinctive odor. Adhesive skin secretions were present in burrowing frogs of three genera. Defensive calls were emitted by Most hylids but none of the myobatrachids. We offer a hypothesis of mimicry to explain the beha vior pattern of exposing the bold black and white ventral surface in Pseudo phryne and Crinia species.