Museum scientists are taking action to restore California Red-legged Frog habitat in Baja California in response to massive declines in their population.

The California Red-legged Frog was once a prominent member of freshwater communities across Southern California and northern Baja California. Today it is almost gone from the southern half of its range due to numerous issues ranging from the introduction of non-native predators to the fungal skin disease known as chytrid. Only 10 remnant populations found in remote regions of Baja California remain. Of these, nine have fewer than 20 individual frogs.

Museum collection data and observations from citizen scientists (compiled together in the Amphibian and Reptile Atlas of Peninsular California) shows evidence of a decline of the species dating back to the 1920s.

Last year, rather than watching more populations blink out, the frog recovery team took action and excavated two new breeding ponds and restored another at Rancho Meling in the Sierra San Pedro Martir. With restoration of frog habitat ongoing at one location, scientists are now turning their focus to the eight remaining populations in trouble, some in ponds as small as backyard swimming pools. With every effort and new pond, the available habitat can more than double their breeding area.

Initial results are positive. The new ponds have been quickly colonized, and multiple breeding pairs were active in the restored pond.  

Rediscovery of California Red-Legged Frogs in the Sierra San Pedro Martir in Baja California and the three-year effort to document these populations has now turned to actively improving their habitat with plans on reintroductions throughout their former range, including bringing them back to Southern California’s freshwater ecosystems.

Posted by The Nat.