Pump failure kills more than 1 million chinook salmon at Idaho hatchery
More than 1.2 million tiny juvenile chinook died at the Rapid River Hatchery earlier this month, a loss that could be felt by anglers from the mouth of the Columbia River to Riggins in the coming years.
According to an Idaho Fish and Game news release, a pump that supplies oxygenated water to an early rearing and incubation building at the hatchery failed, as did an alarm system designed to alert hatchery workers to such mishaps.
The young, inchlong fish were the offspring of adults that returned this spring and were spawned in the late summer and early fall.
They would have been released in 2027 to migrate to the ocean. Those that survived the journey and their time at sea would have returned over the following three years, with most coming back in 2029.
The dead fish represent about one-third of the annual production of the hatchery that aims to boost sport and tribal fishing and mitigate lost fisheries following construction of the Hells Canyon Complex of dams on the Snake River. The hatchery is owned by Idaho Power and operated by Idaho Fish and Game.
According to the news release, hatchery workers were able to turn on an auxiliary pump to save the remaining fish. They are monitoring it around the clock until the cause of the pump and alarm failure can be pinpointed.
Fisheries Bureau Chief Lance Hebdon said it is too early to know if the losses can be backfilled from hatcheries on the Clearwater River.
“We don’t quite have all of that worked out,” he told the Lewiston Tribune. “We will look for opportunities to offset the losses at Rapid River but we are in that kind of zone where people are figuring out what they have in terms of eggs hatching. It is going to take us until next year to iron out if we can move fish from other places.”
Because genetics play a role in how and when different strains of salmon return, fisheries managers are careful about moving fish between river systems.
But Rapid River Hatchery and the hatcheries on the Clearwater River share the same strain of spring chinook, with the hatcheries often backfilling for one another.
Becky Johnson, production director for the Nez Perce Tribe’s Department of Fisheries Resources, said this year’s brood class of spring chinook at Dworshak, Kooskia and Nez Perce Tribal hatcheries are months behind the fish at Rapid River Hatchery and the Clearwater Hatchery that is operated by the state.
“We develop them a little slower on colder water. We won’t know for a while what we’ve got,” she said.
Production levels at the hatcheries and releases from them are directed by negotiations under a U.S. v. Oregon court case that dates back to 1969. If there are extra fish after those obligations are satisfied, backfilling can occur.
“We will look at all options,” Johnson said. “Everybody is well aware that it is a really important hatchery on the Snake and Columbia that actually provides a lot of harvest from the Columbia all the way back to Nez Perce Country.”