The federally threatened California red-legged frog (Rana draytonii) once inhabited ponds and wetlands from Mendocino County to Baja California. Now eliminated from 70 percent of its former range, it primarily lives in coastal drainages from Marin County south to San Simeon. There are still sizeable populations in Point Reyes National Seashore and Golden Gate National Recreation Area, and an effort to re-establish a population at the Bear Gulch Reservoir appears to have stabilized the population in Pinnacles National Park.
A number of things led to the California red-legged frog’s decline. In the mid-1800s, they were intensely harvested to satisfy a booming culinary demand for frog’s legs. Widespread draining of ponds and wetlands for development and agriculture over the past 150 years has also destroyed much of their habitat. Numerous non-native plants and animals have been introduced into what remains—in particular, introduced bullfrogs and fish that prey on the frogs have significantly contributed to the frogs’ decline.
Mori Point and Muir Beach in the Golden Gate National Recreation Area are prime examples of areas where red-legged frogs have been affected by human disturbance. At Mori Point, intensive recreation and a large network of informal trails had eroded the landscape and altered its hydrology. At Muir Beach and the nearby Banducci flower farm, frog habitat had been lost to centuries of agriculture and development.
The National Park Service and their partners have been working together on extensive restoration projects at both sites to improve trail systems, construct ponds and wetlands for breeding frogs, and restore native vegetation. They have been monitoring the frogs to see how the they respond to these changes, and have also done some radio tracking at Mori Point to learn more about how red-legged frogs move across the park’s landscape.
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Last updated: November 8, 2018