Partitioning Patterns of Amphibian Larvae in Response to Stream Characteristics in the Russian River Watershed
This series profiles the work of WATERS grant recipients. Grants are made possible through a CEI partnership with Sonoma Water.
As climate change alters landscapes of the North Bay, scientists have begun studying amphibians as a way to assess the health of creeks and other waterways.
Throughout California, rainfall patterns are changing, “with trends toward fewer, more extreme rainfall events in the winter and longer, drier, hotter summers,” wrote SSU Biology professor Derek Girman. Girman and his student team are studying frogs and salamanders, species that are most sensitive to these changes.
During the summer, “streams are at risk of transforming into a series of intermittent pools, which has the potential to completely alter the form and function of the stream environment on which amphibian egg and larvae development depend,” wrote Girman.
SSU graduate student Beth Sabo is leading a team of student volunteers to survey three regional streams for eggs and larvae of six species of frogs and salamanders.
“My study will provide important baseline information about the egg masses and larval stages of locally abundant amphibians, capitalizing on this moment in time when they are still relatively abundant,” Sabo said. “Once scientists have baseline information, different hypotheses can be posed and answered, such as potential impacts of climate change on these aquatic animals.”
Sabo and the team spend hours in local streambeds. “I am currently in the field almost daily, collecting data for my project. I tell my friends and family that ‘I’m living in the streams,’” Sabo said.
We “palpate under boulders in search of egg masses and use a GoPro camera to seek out discreet potential egg deposition locations,” said Sabo. “So far, the process is incredibly fruitful. We have found many more egg masses than expected.”
In addition, the team has been gaining valuable insight on the preferred egg-laying habitat of red-bellied newts (Taricha rivularis) and Foothill yellow-legged frog (Rana boylii).
Frog eggs, for example, are usually found attached to the downstream edge of a cobble-sized rock. Because the team looks under every single boulder, they have found some surprises.
“We’ve been finding frog eggs in unexpected, or atypical, locations. Buried under the ledge of a boulder, perpendicular to stream flow… There is one boulder that was home to BOTH frog and newt eggs!” said Sabo. “These little surprises can help biologists understand where to look and how to conduct more complete surveys for the species. The more we know about atypical egg laying habits, the better we can understand the range of behaviors for each species.”
Sabo is also making observations on the health of the eggs. “I noted some disease on the egg masses of red-bellied newts. On some egg masses, there appears to be a mold on the outer jelly layer of the egg, or the embryos appear swollen, white, and will likely not survive,” said Sabo. “Diseases and loss are a fact of life for all species, but noting and tracking disease spread and expansion in sensitive species can help us better understand how to support these animals in an uncertain future.”
The sites where this research is being conducted are in native Pomo, Miwok, Coast Miwok and Wappo territory and include: the Modini Maycamas Preserve, the Bouverie Preserve, and Sugarloaf Ridge State Park. These partners will be given the results of this research as part of collaborative efforts to manage and care for the lands and waterways.
Student contributions have been integral to the project, and undergraduates are gaining professional experiences as part of the project. “The collaboration with these community partners also provides excellent opportunities for SSU students to receive valuable training in techniques relevant to careers in environmental conservation so they can continue to impact society and science in their future endeavors,” wrote Girman.
The study is funded by the WATERS Collaborative. Funding from WATERS helped the team purchase the GoPro being used in this research. WATERS is a collaboration between Sonoma Water and The Center for Environmental Inquiry that engages people from all backgrounds and disciplines in finding solutions to water challenges facing the North Bay.
The Center for Environmental Inquiry mobilizes faculty, students and community to solve environmental challenges of the North Bay. To get involved; learn more about our programs, classes, or projects; or to donate, contact Center Director Claudia Luke at lukec@sonoma.edu (link sends e-mail) or visit cei.sonoma.edu.