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Postmetamorphic California Red-Legged Frogs have a highly variable animal food diet (Hayes and Tennant 1986), with much variation seemingly related to the ability of the different-sized frogs to handle different-sized prey. Generally, postmetamorphic R.a. draytonii seem to take any prey available they can subdue that are not distasteful, with larger frogs able to make both larger prey and greater range of prey sized. Amphibians and small mammals may contribute significantly to the diet of adult and subadult R. a. draytonii (Hayes and Tennant 1986; see also Arnold and Halliday 1986, Baldwin and Standford 1987). Adult frogs appear to use vibrations transmitted along willow branch run ways that lie near water levels to detect approaching small mammal prey (see Hayes and Tennant 1986; pers. Observ.) (Jennings, Hayes and Holland Petition 1992). So it is clear that the California Red-Legged Frog needs to make use of what limited habitat is left in order to obtain food matter. If the size of the California Red-Legged Frog habitat continues to decrease so will the population. It is also estimated that the Adult R.a. draytoniii also seem to use vibrations transmitted along the willow branches or vegetation upon which they are resting to detect the approach of certain predators (e.g., raccoons, black bears, humans; pers. Observ.) (Jennings, Hayes and Holland Petition 1992). Currently the California Red-Legged Frogs do not appear to have any scarce resources or competition with other species. |