Gold dots and blue squares indicate where native frogs are presumed extinct. No habitat loss hypothesis adequately explains why this frog survived with current land-use practices for over 50 years before its decline. It is still abundant in California only in the northern third of its range on lands under federal ownership. Most populations were apparently healthy until the mid-1970's, when a population crash occurred in southern California and the Sierra Nevada foothills after several years of severe floods and drought, which may have been responsible for the declines, although it is not certain. Historical and current distribution of the foothill yellow-legged frog, spotted frog, and Yavapai leopard frog in California based on 3,316 museum records and 171 records from other sources.
Dots indicate locality records based on verified museum specimens.
Red dots and green squares denote localities where native frogs are extant. Gold dots and blue squares indicate where native frogs are presumed extinct. It appears to be on the verge of extinction in California. It has not been seen in the state since the mid-1960's and now seems to be extinct at all sites examined. Most localities where this frog was historically found have not changed appreciatively during the past 50 years, so the reasons for the species' decline and disappearance remain a mystery.