Beavers are the quintessential ecosystem engineer, significantly altering the landscapes where they live and creating a rich diversity of habitats that countless wildlife species depend on. Beavers may become even more important for wildlife, especially amphibian species, as the climate warms and permanent ponded habitats dry up. Ponds that stay wet year-round are particularly important to frogs and salamanders, which rely on constant moisture to survive. However, many permanent water habitats also contain fish, which prey on amphibians. To find a happy-medium habitat with refuge from predators and refuge from drying waters, amphibians rely on specific habitat characteristics which may become more difficult to find under warming conditions. Beavers may engineer the exact kinds of habitat amphibians need, with enough permanent water to survive a hot climate and enough shallow margins, side-pools, and habitat complexity for amphibians to escape predatory fish. These dynamics are important in the context of restoration work conducted by the Tulalip Tribes, Washington Department of Fish and Wildlife, and organizations like Methow Beaver Project and Trout Unlimited, who work to re-establish beaver populations on the landscape and increase beaver-engineered habitat. Understanding where this beaver-based restoration will have the biggest impact for vulnerable amphibian species will inform priority areas to re-establish or promote beaver populations.

To determine priority areas for beaver-based restoration in the Northwest, Julianna’s research will show the relative importance of beaver ponds for amphibians in a wet ecoregion compared to a dry ecoregion. She will use Washington State’s Cascade Mountains as a natural laboratory to compare amphibian populations in beaver sites in a high-precipitation climate (on the west slopes of the Cascades) with amphibian populations in beaver sites in a low-precipitation climate (on the east slopes of the Cascades). In these two areas, Julianna will be answering the questions: Do beavers benefit amphibians and salmonids? Do beavers facilitate their coexistence? Do these effects differ between wet and dry ecoregions?

She expects to see greater amphibian dependence on beaver ponds in the low-precipitation climate, and she expects beavers to create habitat in which predatory fish and amphibian populations can coexist, even in low-water environments, where both fish and amphibians are under environmental stress. If beavers can support multiple taxonomic groups under climate stress, this research will support restoration work focused on beaver reintroduction and population enhancements in dry, climate-stressed ecosystems. The results will be shared with restoration partners at online and in-person working group meetings, and a database of sites surveyed, species observed, and beaver activity will be made available to partners. Ultimately, this knowledge will inform restoration partners’ decisions on where to reintroduce and support beaver populations.