by Grace Graham
Hundreds of thousands of visitors come to our watershed lands each year. Some of the most popular trails on Mt. Tamalpais are those with sweeping vistas, rugged landscapes and beautiful waterfalls. One trail, Little Carson Falls, has the winning combination of all three and, as a result, is one of the most frequented trails on the watershed. However, Little Carson Falls is not just a popular gathering place for people. It also holds the trifecta of cold water, slow velocity flow and abundance of cobble substrate, which makes it ideal habitat for the foothill yellow-legged frog. The resulting overlap of heavy foot traffic and delicate breeding habitat at Little Carson Falls could spell trouble for a species that is already in decline.
The foothill yellow-legged frog is listed as both a federal and state species of “special concern.” It has disappeared from more than 45 percent of its historic range in Oregon and California due to habitat loss and degradation, disease and the introduction of exotic predators. In the Mt. Tamalpais Watershed, the breeding habitat of the foothill yellow-legged frog has been reduced from four streams to two due to heavy recreational impacts and exotic predators.
However, the Marin Municipal Water District is training docents to monitor conditions and educate hikers at Little Carson Falls. Last year volunteer docents made contact with almost 800 hikers during some of the busiest weekends in spring and early summer. These docents successfully got dogs on leashes and people away from the water by showing visitors that life existed in the falls and informing them about this special, at-risk species.
Docents are asked to commit to a minimum of two five-hour shifts between March 15 and May 15, when eggs and tadpoles are at their most vulnerable. Docents should be prepared to hike three miles round-trip over steep terrain. Little Carson Falls is located in Marin County, about five miles outside of Fairfax. Training for the 2011 season will take place at the Sky Oaks Watershed Headquarters from 9:00 a.m. to 2:00 p.m. on Saturday, February 26. To become a frog docent, please call our volunteer hotline at (415) 945-1128 or email email@example.com.