It’s an annual one-day operation, but what comes of it will help the Lower Elwha Klallam Tribe learn more about Lake Sutherland kokanee.
The tribe has been studying the landlocked sockeye salmon within the Elwha River watershed for four years, including the population’s health and genetics. The purpose is to gather baseline data of the population before the river’s fish-blocking dams are removed starting in 2011. The lake is connected to the river via Indian Creek.
Like sockeye, kokanee spawn only once in their life cycle, and typically spawn in rivers and streams that are tributaries to lakes but also on lakeshores, mainly where groundwater comes up through gravel.
Unlike sockeye, kokanee spend their entire lives in freshwater. Because they don’t migrate to sea to feed, kokanee are much smaller than their anadromous sockeye cousins.
“After the dams are removed, we’ll continue this effort and see if anadromous fish begin to use Lake Sutherland, and see if there is change in the health profile of the kokanee,” said Larry Ward, the tribe’s hatchery manager.
It’s possible that the kokanee may leave the lake and head for the Strait of Juan de Fuca after the dams come down, but it is more likely the fish will stick to the freshwater, Ward said.
“Having a solid database of the health of the kokanee will help us keep tabs on the health of the watershed,” Ward said. “It’s all part of learning more about the enormity of the Elwha River system and what species have what roles in it. The database we are building is incredibly valuable on its own, but more so if anything were to happen to this population.”
Fish pathologists from the Northwest Indian Fisheries Commission and U.S. Fish and Wildlife Service sample the fish for diseases and to develop genetic profiles. Special attention is paid to looking for Infectious Hematopoetic Necrosis (IHN) to which sockeye are susceptible. It’s a fish disease that causes death by destroying blood-forming tissues such as the kidney and the spleen.
Further work is being conducted by a biologist from Canada’s department of Fisheries and Oceans who is studying a fish parasite unique to the Lake Sutherland kokanee. The parasite doesn’t appear to be harmful to the fish, but further studies are being conducted.
