Salmon counts are essential for assessing populations and managing fisheries, but current approaches for counting salmon are logistically challenging, and counts are increasingly interrupted by floods and funding gaps. We are testing a complementary method for assessing the strength of Chinook and chum salmon spawning runs by quantifying their DNA in river water. Our colleagues at the Tanana Chiefs Conference, Alaska Department of Fish and Game, and U.S. Fish and Wildlife Service collected daily environmental DNA samples alongside conventional salmon counts at five established salmon assessment sites in the Yukon River Basin. We have quantified Chinook and chum salmon DNA concentrations in these samples and are now testing statistical models for estimating salmon counts from eDNA and environmental covariates. This project is led by grad student Maggie Harings and funded by the Alaska Climate Adaptation Science Center, National Science Foundation, and National Institute for Water Research. Find more information on our project website.

Building on our Yukon salmon eDNA research, our colleagues at the Kuskokwim River Inter-Tribal Fish Commission asked us to help them test eDNA-based methods for assessing salmon runs in the Kuskokwim Basin. KRITFC, Alaska Department of Fish and Game, and U.S. Fish and Wildlife Service staff collected daily environmental DNA samples alongside conventional salmon counts at three salmon weirs on Kuskokwim River tributaries over two years. We are quantifying Chinook and chum salmon DNA concentrations in these samples and testing statistical models for estimating salmon counts from eDNA and environmental covariates. If effective, this tool could be used to complement weirs and facilitate new community-led monitoring projects in the region. This project is led by Research Associate Brandi Kamermans Cron and funded by the Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative and UA's Arctic Leadership Initiative.

Healthy salmon runs need productive, high-quality habitat in both the ocean and in the watersheds that support spawning and rearing. But habitat restoration is expensive, so where should we focus our efforts to provide the most benefit in a warming world? To address these questions, we are working with the Yukon River Drainage Fisheries Association and UAA to document, quantify, and map the cumulative effects of changes in climate, species interactions, and habitat quality on Yukon River salmon. Our goal is to identify the most effective local and regional actions to support salmon recovery and resilience of salmon-dependent communities. We will consider how cumulative effects of warming temperatures, changes in streamflow, species interactions, and habitat quality interact to influence the ability of salmon to recover from their recent population declines. This project will support both agency-led habitat restoration projects, such as culvert replacement and mining restoration, and Tribally-led efforts to revitalize traditional salmon stewardship practices, such as seasonal harvest of pike and other salmon predators, and maintaining fish passage along streams influenced by beaver. Grad students Raven Dawson and Kristen Reece are leading the project. Other partners include the Yukon River Inter-Tribal Fish Commission, Tanana Valley Watershed Association, US Geological Survey, Bureau of Land Management, US Fish and Wildlife Service, and Alaska Department of Fish and Game. This project is funded by the Alaska Climate Adaptation Science Center.

Arctic ecosystems are made up of species that have evolved with each other in an extreme environment, many of which provide food and livelihoods for people. It is critical to know how Arctic species will respond, along with their ecosystems, to rapid change. Will ecosystems fall apart, muddle along in a reduced state, or can species adapt to keep pace with a changing environment? The Evolving Meta-Ecosystems (EVOME) Institute brings together experts from across biological disciplines to generate new insights at every scale of biology, from genes to landscapes. Our team at UAF is studying the thermal performance and trophic interactions of Arctic grayling in close coordination with other teams studying willows, insects, and birds within the broader EvoME Institute. Our study sites stretch from the Arctic Coastal Plain over the Brooks Range and south into the Koyukuk River Basin. Grad students Matt Zimmerman and Roberto Ponce Velez are leading our grayling work. This project is funded by the National Science Foundation.

Coastal communities along the Gulf of Alaska rely on fish and other aquatic resources that are fluctuating in a changing environment. The Interface of Change project is working to investigate the resilience of these species that are critical to the subsistence way of life as well as developments in the mariculture economy. Within this large project, our team is working to understand how anadromous fish like salmon and hooligan are responding to environmental drivers, and what communities can do to build resilient economies and food systems. We reached out to Tribes, agencies, and non-profits to hear their priorities for this research, and we heard a major shared interest in understanding how changing environmental conditions are affecting sockeye salmon production in glacial and non-glacial systems. We are especially interested in how changes in glacial meltwater, water temperature, and turbidity might be influencing sockeye smolt rearing capacity in lakes. Grad student Matt Piché is leading this work, building on his years of expertise studying salmon in the Copper River and Prince William Sound for the Native Village of Eyak. This project is funded by the National Science Foundation through the Alaska EPSCoR program.