Field reports: Gillnetting targets region’s northern pike invasion

FISHING – Northern pike appear to be gaining a foothold in the upper reaches of Lake Roosevelt according to preliminary results from a six-day gillnetting survey that concluded Tuesday.

Gillnets have been deployed to sample and control non-native northern pike from the Pend Oreille River to the Kettle Falls area of Lake Roosevelt.

The Spokane Tribe is being funded by the Northwest Power and Conservation Council for sample gillnetting on pike in the Columbia River near Kettle Falls. The invasive predators have shown up in increasing numbers in the past three years.

In the Pend Oreille River downstream from Newport, the Kalispel Tribe – in cooperation with Washington Department of Fish and Wildlife – will deploy nets for the fifth season of suppression. The nets will be deployed Monday through Friday from March 1 to May 1.

Lake Roosevelt is the new frontier of concern about invasive pike, fisheries managers say. In a week of surveying last March, Spokane Tribe staff deployed 87 gillnets and caught 21 northern pike.

“That’s not many fish,” said Brent Nichols, the tribe’s Lake Roosevelt fisheries program director. “What’s troubling is the two distinct age classes we found: 11 fish were one year old and 10 fish were two years old, indicating they could be starting to establish potential breeding populations.”

This year’s survey provided a more startling look at the pike invasion.

The gillnet survey ending Tuesday bagged a total of 71 northern pike in the Kettle Falls survey area – more than three times the number captured last year.

“We haven’t completed the aging data yet, but judging by size it looks as though there are at least three age groups of pike,” Nichols said. “We got some large fish this year.”

• Anglers were proving that bigger fish were in the system last year.

The survey area is up and downstream from Kettle Falls with emphasis near the mouth of the Kettle River, he said.

“We found some pike with 13-inch walleye in their bellies,” he said. “They’re eating salmonids (trout), too.”

The survey was conducted before the lake’s pre-runoff drawdown occurs.

“We want to get a better handle on the situation,” Nichols said, noting that the tribe hasn’t justified or been funded for pike suppression, yet. “We may do some more targeted netting over the next couple of weeks based on what we found this past week.

“We’ll be trying to get information to develop a longer term suppression plan to keep pike from establishing in Roosevelt and moving farther down the river.”

“We have a bottleneck in the Kettle Falls area; maybe we can hold them off there.”

Meanwhile, the Kalispel Tribe will be targeting the Pend Oreille’s Box Canyon Reservoir pike for a month at the entrances to sloughs and other likely spots as the fish stage to spawn, said Jason Olson, pike program manager.

“We’ll follow up in May with a week-long survey with nets sent randomly to get the density of pike remaining in the river,” he said. The goal is to keep the population low enough to curb its spread downstream into Canada and into the Columbia.