[3][5] A federal rule to list four out of six extant distinct population segments (DPS) under the Endangered Species Act was proposed in December 2021.

These frogs can be identified by their rough skin, horizontal pupils, fully webbed hind feet, and their habit of jumping into moving water.

As the species grows older, it changes its diet to animal tissue which must be swallowed whole because the frog's jaw is structured on a hinge joint that does not allow for sideways movement as in humans.

Adult frogs eat a range of foods such as moths, ants, grasshoppers, hornets, beetles, flies, water striders, and snails.

Previously believed to mate from March to May, recent experiments have shown the time to be closer to April to late June.

The former secretes a milky substance that fights against fungal infections and the latter uses its capability to have males turn blue during mating season.

Exposure to carbaryl, a substance found in common pesticides, has been shown to not kill the frogs but does lower the peptides' abilities to defend the species against invaders like the chytrid, B.

[7] One study suggests the "data from a comparably sized undammed river fork in the same system ... demonstrated that both the number of potential sites and the total number of egg masses were…higher on this fork than in our main stem", so the unseasonal flooding required by the dam was negatively affecting the mating behavior of the frog.

[17] Therefore, the colder temperatures are making it more difficult for the frogs to grow quickly, which sometimes leaves the species prey to many other animals that feed on their young.

This species is also estimated to be gone from most of its range in the Sierra Nevada, especially south of Highway 80, where pesticides often contaminate rivers, and dams block the essential stream flows.

[18] The foothill yellow-legged frog is a natural prey of diving beetles, water bugs, garter snakes, rough-skinned newts, bullfrogs, and western toads.