Young salmon released early due to debris

LEWISTON – Nez Perce Tribe fisheries managers prematurely released hundreds of thousands of juvenile Chinook salmon into the Clearwater River in north central Idaho after debris from flash floods clogged a hatchery filtration system and put the young fish in peril.

“We got them out into the river and gave them a better chance,” said David Johnson, director of the tribe’s fisheries program.

A series of spring flash floods deposited debris in the fresh water intake of the tribal hatchery at Cherry Lane, east of Lewiston, and prevented fresh water from circulating in holding ponds.

Workers recently released 400,000 juvenile spring-run Chinook and 900,000 juvenile fall-run Chinook into the river to avoid suffocating them.

The fall-run fish were scheduled to be released into the Clearwater from the hatchery in early June, so Johnson anticipated they have a good chance of survival. But the spring-run Chinook were not scheduled for release until July into the Selway River upstream from the Clearwater.

“The really early releases, I would say, are going to have the hardest time,” he said.

Meanwhile, hundreds of thousands of hatchery raised fall-run juvenile Chinook were released Tuesday and Wednesday into the Grand Ronde River in Oregon and Washington under an agreement between the Nez Perce and Umatilla Indian tribes and the U.S. Fish and Wildlife Service.

Fisheries managers hopes the juvenile fish will swim to the ocean and one day return to spawn in the Grand Ronde, re-establishing a salmon run that was depleted by the construction of dams downstream on the Snake River.

Biologists say adult Chinook returning from the ocean to the Snake River system have begun spawning in tributaries where they were not originally released, with 250 Chinook spawning beds counted last year on the Grande Ronde.

“Because of all the other releases and improving survival and all these other things, fish are now wandering into areas where they may not have hatched,” said Glen Mendel, regional fisheries manager for the Washington Department of Fish and Wildlife at Dayton, Wash.