Biologists trap wayward salmon near Woodland
State biologist Mike Eikan got a workout on Wednesday as he hauled bags filled with water and flopping salmon 100 yards up a muddy hill.
“Man, that’s a big one,” he said with a grunt as he hoisted a bag with a 40-pound, hook-jawed male Chinook into a bubbling tank towed on a trailer behind a pickup.
Eikan and a team of fisheries biologists were busy Wednesday at a large drainage ditch near the Sacramento River in the Yolo Bypass in what’s become an annual routine during the state’s drought.
They were trapping wayward fish that had swum off course into the canal during their annual migration and were moving them back into the river.
“They’re having problems with the drought identifying which route to go right now,” said Colin Purdy, a senior environmental scientist with the Department of Fish and Wildlife. “Instead of going up the Sacramento River, they’re taking a left, essentially.”
Beginning in 2013, halfway into the state’s four-year drought, the department first began noticing more fish were getting stuck in the massive system of irrigation canals connected to the Sacramento River.
That spring, biologists discovered that some 600 endangered winter-run salmon had gotten trapped 70 miles off course in the Colusa Basin Drain, a system of ditches and channels that carries runoff from more than 1 million acres, much of it rice fields in Glenn, Colusa and Yolo counties.
Although conservationists captured and returned many of the fish to the river, some Chinook were so stressed from the experience they were unable to spawn. State officials estimate that nearly 50 percent of the winter run was lost.
“That really shocked a lot of the resource managers,” Purdy said. “Since then, we’ve started building seasonally these traps that we can put in the channel to allow us to collect fish and move them pretty efficiently.”
Over the past three weeks, the biologists at two fish traps have corralled and moved close to 500 fish, most of them non endangered fall-run Chinook.
The traps are a temporary solution, but efforts are underway to permanently stop the fish from going off course. This summer, local, state and federal officials completed a $2.5 million project that permanently blocked the fish from entering the Colusa Basin Drain in Knights Landing. A similar barrier project is planned for next year, close to where Eikan and his team hauled fish.