South Fork EelYellow-Legged Frog

Survey: Benbow AreaApril 18, 2015

Researcher/Teacher

Dr. Sarah KupferbergHerpetologist

Report by:

Pat HigginsERRP Volunteer Coordinator

Dr. Sarah Kuperferberg is a graduate of UC Berkeley and has been studying the Eel River for 15 years. She lead a group of Eel River Recovery Project volunteers on a survey for yellow-legged frog egg masses on April 18 at Benbow State Park and upstream on the Bureau of Land Management Benbow Recreation Area. Sarah is shown here disinfecting her stream boots so that no diseases are transmitted that could infect frogs.

Males select suitable habitat and make their mating calls underwater to attract females.

The female releases her eggs and the male fertilizes them. The egg masses are attached to the downstream side of a rock and quickly expand in size.

Tadpoles hatch in about 10 days to two weeks, and they turn into frogs in early fall.

The maximum age of yellow-legged frogs is 10 years old.

While yellow-legged frogs are in decline elsewhere in California, they are still relatively abundant in the Eel River basin.Photos by Sarah Kupferberg

Pregnant Female 3 yrs.

Tadpole

Young of Year (fall)Eggs

Juvenile: 1-2 yrs

Yellow-Legged Frog Life Cycle

April 18 Frog Team: From right to left is Dr. Sarah Kupferberg, Diane and Pat Higgins, Darcy and Larry Bruckenstein, Michael McKaskle, Lucy and John Davis, and Doug Parkinson.

Sarah Kupferberg found a yellow-legged frog egg mass immediately upon arriving at the edge of the South Fork Eel River and showed volunteers what they look like. This was the only egg mass that was handled during the course of the day.

Sarah counts the number of egg masses per kilometer because it is much more difficult to count more numerous tadpoles and secretive adults.

David Sopjes (center) points out another egg mass, while Sarah marks the location of an egg cluster with a GPS device. Michael McKaskle and Diane Higgins observe.