Fish & Game easing up on lake trout netting

PONDERAY — The Idaho Department of Fish & Game is downshifting its lake trout suppression efforts on Lake Pend Oreille this year.

The department initiated a two-pronged suppression program in 2006 in a bid to save the lake’s once-imperiled kokanee population. It paid anglers cash incentives to harvest lake trout and contracted commercial-scale netting operations.

Over the ensuing nine years, netting removed 98,113 lake trout and anglers removed another 79,016 fish, resulting in a grand total of 177,129 lake trout, according to Andy Dux, principal fisheries biologist for Fish & Game.

Gill netting, in particular, resulted in an 80-percent decline in adult lake trout and a 77-percent decline in juvenile lakers.

“We’ve been able to hit really all size classes of the population,” Dux told anglers at the annual State of the Lake presentation on Thursday.

The steep reductions in the lake trout population brings about a new phase in the suppression program.

“Our plan now is to start gradually taking out pieces of that program and reducing our netting effort. We’ll be doing it in small chunks so as not to go the wrong direction and we’ll be monitoring very closely what the population does in response,” Dux said.

This year, the netting program is being scaled back from 30 weeks to 25 weeks. Current netting operations are set to suspend in April, resume in September and extend into December.

It’s the first time Fish & Game has eased off the gas pedal since the suppression program was first put into place.

The abundance of adult kokanee continues its upward trend. There were nearly 1.5 million adult kokanee in the lake in 2014.

“It’s one of the highest adult estimates that we’ve had in the history of this time period we’ve been monitoring — the highest number we’ve seen since the early ‘90s,” said Dux.

In 2013, there were barely a million adults and less than half that many in 2012, according to Fish & Game figures.

The kokanee fishery was reopened to harvesting and last year the Idaho Fish & Game expanded the bag limit from six to 15 fish per day.

The abundance of kokanee is also helping improve the lake’s trophy rainbow trout fishery. Fish & Game conducted a growth survey which indicated rainbows are gaining in weight and length when compared to 2006 survey results.

“Those fish are in better shape than they were a few years ago, which is what we expected to see given how many more kokanee we have out there. Their food source is a lot more abundant,” Dux said.

Dux said the lake’s rainbow trout are similar in size to the fish that anglers encountered in the late 1970s and early 1980s.

“Given we’ve got more kokanee, we have the potential for this to even increase some more,” Dux said of rainbow trout sizes.