Kokanee Outlook Improves in Lake Pend Oreille

The future for kokanee in Lake Pend Oreille looks better today than it did a year ago.

Efforts to reduce predators, however, must be sustained to restore the popular kokanee and rainbow trout fisheries, Idaho Department of Fish and Game officials say.

“We finally have some encouraging news in the battle to save Lake Pend Oreille , but we are not out of the woods yet,” said Ned Horner, regional fisheries manager with Fish and Game.

Recent analysis of Lake Pend Oreille population data by Mike Hansen, a University of Wisconsin professor and lake trout expert, demonstrates that between the use of angler incentives and trap nets, the mortality rate of lake trout has been dramatically increased. This effort must be continued to be successful, but taking a bite out of the predator population is affecting the lake’s kokanee.

Anglers took 10,800 lake trout and 5,800 rainbow trout through an angler incentive program. Another 4,800 lake trout have been taken through a netting program.

Adding natural mortality, about 35,800 lake trout have been removed from Lake Pend Oreille for a 59.5 percent annual mortality rate. Rainbow trout are not targeted by the netting program, so the mortality rate of rainbow trout is substantially lower.

“We believe the mortality rates of lake trout that we are seeing are likely high enough to offset recruitment,” Horner said. “Now it is essential that we sustain the effort to have long term success.”

Angler cooperation has been essential to the gains made to date. Anglers receive a monetary reward for catching lake trout or rainbow trout from the lake. Daily bag limits on both species have been suspended.

“The multiple methods of angling and netting are aiding in the suppression of predator numbers, giving kokanee a chance to rebound,” Horner said.

The initial incentive of $10 per fish was increased to $15 per fish on December 1 to encourage anglers at a time of year when fishing activity typically declines.

Horner is encouraged.
“There are good numbers of kokanee fry in the lake, and fairly good numbers of one year old fish. [Fish and Game] has collected nearly 12 million kokanee eggs to rear at the Cabinet Gorge Hatchery for release in [Lake Pend Oreille] in 2007. With the continued help of concerned anglers taking the hungry mouths of predators out of the lake, it appears we can still pull out of this unbalanced condition,” he said.

Kokanee season in Lake Pend Oreille is catch-and-release only.