Coho Salmon

Coho salmon are the second largest of the Pacific salmon. They can reach lengths of 35 inches and weigh more than 30 pounds. They are also referred to as silver salmon. In the ocean, coho salmon have dark metallic blue or greenish backs with silver sides and a light belly. Fish spawning in freshwater are dark with reddish-maroon coloration on the sides. Prior to the 20th century, large numbers of coho returned annually to the Wenatchee and Methow rivers. However, impassable dams, commercial overfishing, unscreened irrigation diversions, and habitat degradation all contributed to the virtual disappearance of coho in these rivers. More recently, efforts have increased to reintroduce Coho salmon to the mid and upper-Columbia River.

Under requirements outlined in our Salmon and Steelhead Settlement Agreement, Grant PUD co-funds the Mid-Columbia coho reintroduction program in collaboration with the Yakama Nation. This program seeks to restore Coho salmon to the Wenatchee and Methow river basins. Over the next 20-25 years, the proposed project would develop a locally adapted, self-sustaining population of coho in the Mid-Columbia Basin, capable of supporting harvest. To do this, the program would use a combination of existing and new facilities. Hatcheries and acclimation facilities used in the feasibility studies would continue to be used. In addition, a new small hatchery in the Wenatchee Basin is proposed, and a few existing ponds or side channels would be modified and new ones constructed to serve as semi-natural rearing and acclimation areas for juvenile coho salmon. A coho salmon reintroduction program intended to develop a locally adapted and naturally spawning population from lower Columbia River stock has been implemented by the Yakama Nation. Grant PUD entered into a 10-year funding agreement with the Yakama Nation to assist in developing their Mid-Columbia Coho Restoration Program. This $7.4 million agreement is for the period 2008-2018.

As a result of the coho program, coho salmon redds and carcasses have been observed in the Wenatchee and Methow rivers. However, the extent to which natural production is occurring has not yet been determined. As more information becomes available and the future of this population has been reviewed and discussed, a decision can be made regarding the long-term management of UCR coho salmon. Grant PUD will work with the PRCC HSC to adaptively manage the coho program to achieve program goals and objectives. Until that time, survival studies for coho through the Project are not proposed.

Species

Sockeye salmon

Number of fish released

Approximately 365,000 smolts

Fish release location

Wenatchee and Methow river basins