Findings from the Eel River Recovery Project (ERRP) were recently featured on the front page of the Mendocino County Observer. The ERRP have performed yearly surveys of non-native Sacramento pikeminnow populations in the South Fork Eel River from 2016-present. Working with UC Berkeley students Phil Georgakakos, Wes Slaughter, Taylor Schobel and Sage Kurnie along with Dr. Brett Harvey of the US Forest Service Redwood Science Lab, the 2018 survey found that the 2013-2015 drought has led to an uptick in large adult pikeminnow, and management of these populations is recommended in order to protect native salmon, steelhead, and others. The full article can be viewed here: 7-12-18 Observer Please also visit the ERRP website, www.EelRiverRecovery.org, to see photos and videos of the 2018 survey and learn how you can donate to the cause.
Dr. Sarah Kupferberg’s research is focused on food web ecology, amphibian population biology, and conservation of aquatic ecosystems in California. A particular interest of Dr. Kupferberg is the effects of dams and diversions on the physical and biotic conditions for wildlife. To investigate these issues, she conducts field research and experiments in rivers with hydroelectric projects, drinking water reservoirs, and flood control projects. Dr. Kupferberg is also applying her extensive knowledge of aquatic ecosystems at the policy level, reviewing stream restoration plans and working with engineers to facilitate designs that are compatible with hydraulic and biological needs.
Angelinos and Eel River Recovery Project volunteers have worked together with Dr. Kupferberg to count (and rescue!) egg masses of Foothill Yellow-legged Frogs (Rana boylii). R. boylii lay their eggs at traditional oviposition sites in the river every spring. The size of tennis to soft balls, these black-speckled jelly masses are more conspicuous than the adult frogs. What do you notice first in the photo below?
Conveniently for biologists interested in conserving this species (which is currently under review for protection by the Federal and California Endangered Species Act), adult females lay one clutch of eggs each spring. So one egg mass = one breeding female frog. A census of clutches thus provides an index of the total size of the breeding population. Repeating the counts annually can indicate if populations are growing or declining. In the case of the Angelo Reserve, the population has fluctuated over the last 25 years, but remains basically stable. In contrast, since 2012 we have been observing a growing population along the banks of the South Fork Eel- this is where the California State Parks stopped operating the Benbow Dam in 2016 to impound the river and create a summer lake. In the Spring of 2016 in advance of the de-construction of the Benbow Dam, ERRP volunteers (http://www.eelriverrecovery.org/) and Angelinos relocated 100’s of egg masses (10,000’s of thousands of tadpoles!) out of harm’s way. Now that the high flows from winter 2017 have reconfigured the gravel bars at the restored dam site, we will monitor how the frogs respond.