July 29, 2013 – During April, May and early June, large numbers of endangered winter-run Chinook salmon and other species were drawn into channels in the Yolo Bypass and Colusa Basin and died, according to reports by California Department of Fish and Wildlife (CDFW) and National Marine Fisheries Service biologists (NMFS). The total number of stranded fish is unknown but agency biologists said it could be as high as half of this year’s returning population of winter-run. This tragedy is exacerbated by high temperature stress on spawning winter-run caused by mismanagement of limited cold water pools in Shasta Reservoir this year.
State and federal fish agencies have known and documented for almost two decades that up-migrating endangered and threatened fish on the Sacramento River, including winter-run, spring-run Chinook salmon, steelhead and green sturgeon are drawn into the irrigation and drainage waterways of the Yolo Bypass and Colusa Basin from which there is no exit and are trapped. Excepting sporadic rescue efforts, little has been done to address this longstanding problem.
“This is an indefensible failure to protect species hovering on the brink of extinction,” said Bill Jennings, executive director of the California Sportfishing Protection Alliance. “The fact that our fishery agencies have long been aware of this problem but done little to correct it is appalling and borders on criminal culpability,” he said “especially, when there are obvious and workable solutions.”
Large numbers of salmon were identified in the maze of creeks and canals in the Colusa basin west of the Sacramento River. More than 300 fish were rescued from Hunter, North Fork Logan and Stone Corral Creeks, Colusa Trough and Delevan National Wildlife Refuge and returned to the Sacramento River. Because of their degraded condition, there was concern that these fish would not successfully spawn. Stranded salmon were also observed in other creeks, including Willow and Funks Creeks, the main stem of Logan Creek, Provident Main Canal and the North East Drain but no rescues were attempted. Members of the public reported salmon at other locations but CDFW staff were not able to get around to them.
It’s a recurring problem. For example, in 2011, NMFS biologists rescued more than 200 listed green sturgeon, spring-run Chinook salmon and steelhead trout from the Yolo and Sutter bypasses. Many others were not rescued and perished.
Curated from Massive Loss of Endangered Winter Run Salmon