Partners Rally Behind the Kokanee Salmon
Nestled in the Seattle metropolitan area, Lake Sammamish sits in a heavily urbanized watershed with 600 acres of parks and greenspace. More than 1 million people annually visit the Lake Sammamish State Park, which is also home to a curious little red fish called the Kokanee salmon (Oncorhynchus nerka). Unlike most salmon, the kokanee never leaves freshwater, traveling upstream to spawn and then returning to the lake.
Historically, annual kokanee runs numbered in the tens of thousands. Since the 1970s, kokanee have declined dramatically, including the extinction of the early- and middle-run populations.
The U.S. Fish and Wildlife Service (Service) has worked over the last decade to preserve the population, determine why it is declining, and identify solutions to help kokanee runs rebound. The Service is working with King County, State of Washington, Snoqualmie Tribe, and other partners to research and monitoring to document the population's status and impediments to survival.
And there are many ideas about the impediments: Are the habitat conditions in the lake too warm? Are there too many nonnative predators? Are there disease issues? Is urbanization limiting the spawning habitat with streams now blocked by roads?
"We don't know if it's one or a combination of these factors," explains Pat DeHaan, Deputy Project Leader in the Service's Western Washington Fish and Wildlife Conservation Office.
Partners are also considering new strategies to address recent kokanee decline. For example, the Service is exploring different approaches to hatchery propagation, such as releasing the fish a later when lake temperatures are cooler, or releasing the fish when they are more mature and not as vulnerable to predation or disease.
While the population has fluctuated over the years, precariously low numbers of kokanee in 2007 led to the establishment of the Kokanee Working Group, a collaborative partnership among land-owners; local, state, federal, and tribal representatives; and nonprofit organizations.
In 2013, the Service selected the Lake Sammamish basin for one of the first-ever Urban Wildlife Refuge Partnerships (UWRP), the goal of which is to connect city residents to nature. Funding from UWRP helped support the public-private partnership and resulted in the development and implementation of a plan to reach and engage diverse audiences.
"The kokanee are an amazing little red fish," says Kelly Donahue, the Service's Urban Wildlife Refuge Partnerships Coordinator. "And an amazing partnership exists to save this culturally significant species."
Overall, the partnership is implementing a multi-layered approach that features habitat restoration, watershed-scale conservation, climate change research, supplementation, citizen science, and educational programming and information.
While kokanee numbers appeared to be improving in recent years – more than 18,000 young fish returned from Lake Sammamish in 2013 – biologists counted fewer than 20 individuals in a 2017 survey. To address the current low numbers, partners are considering capturing returning spawners for the hatchery, freezing male kokanee semen for future propagation, delaying the release of fish into Lake Sammamish, and releasing kokanee into additional creeks in the watershed.
There is still much to do to help secure a future for the kokanee. Because of its location in a metropolitan setting, the Kokanee Urban Wildlife Refuge Partnership provides a unique opportunity to rally residents and help safeguard this iconic fish, connecting a large population to their nearby nature.
Lisa Pelstring, an advisor of urban environmental issues and the urban waters federal partnership office of water and science, can be reached at lisa_pelstring@ios.doi.gov.