A small army has been raised to fight the presence of Northern Pike in Lake Roosevelt, including the state of Washington, the Spokane and Colville tribes, and the three mid-Columbia public utility districts that own five dams on the Columbia River downstream of Chief Joseph and Grand Coulee dams.
The Douglas County Public Utility District, which owns and operates Wells Dam, the first downriver from Chief Joseph, is watching the pike suppression effort carefully.
While Douglas is not contributing to the current suppression effort, “we stand ready to fund suppression efforts in Wells, should pike be identified in that section of the Columbia River,” utility spokeswoman Meaghan Vibbert said.
“Pike are on our radar for sure,” said Steve Hemstrom, a senior fisheries biologist for the Chelan County Public Utility District in Wenatchee, which owns and operates Rocky Reach and Rock Island dams, the second and third dams downriver from Chief Joseph.
Bill Towey, a fisheries scientist for the PUD, said the utility is very concerned about the Northern Pike presence in Lake Roosevelt and the Columbia River Basin and supports the continued suppression and early detection efforts.
Hemstrom said he’s confident pike will be detected in the fish-passage facilities at the Rocky Reach and Rock Island dams if they entrain over Grand Coulee and Chief Joseph. So far, none has been detected.
While that could change, Hemstrom thinks it is unlikely. Water flows past and through the two dams more quickly than in slow-moving Lake Roosevelt, and the Columbia near Wenatchee has fewer shallow backwater areas pike prefer. Thus, salmon and steelhead smolts move through the area quickly, perhaps too fast for pike.
“We know that pike are not chase predators; they are burst-and-ambush predators,” he said. “So would they prey on salmon that are moving quickly? Probably not. Do the migrating salmon go into backwater places where pike like to hide? Probably not.”
Tom Dresser, of the Grant County Public Utility District, which owns and operates Wanapum and Priest Rapids dams on the Columbia, the fourth and fifth dams downriver from Chief Joseph, said the utility is keeping a close lookout for pike.
“Grant PUD has crews on the water from mid-March through October of each year, five days per week (Monday-Friday),” Dresser said. “If pike were detected, crews can be redirected within a matter of hours to that location to employ suppression and removal efforts. I believe that Grant PUD is in a good position to detect and respond if necessary.”
The experiences of pike investigations in Canada might give some pause, however. Canadian researchers found pike are extremely adaptable and able to easily survive along rocky shorelines and in fast-moving rivers, not only in their preferred habitat of shallow lake and river waters. If there is a likely spot where pike might take hold downstream of Chief Joseph, a sort of point of first contact, a wide spot along the north shore of the river called Lake Pateros, after the adjacent city, Pateros, is a good candidate. Biologists are watching it carefully. The habitat there is similar to the areas around the mouths of the Kettle and Colville rivers in Lake Roosevelt that pike prefer.
Juvenile pike from the mouth of the Colville River
Salmon and steelhead spawn in Columbia River tributaries, and those fish might be affected by pike if they get below Chief Joseph, a potential the Chelan PUD recognizes.
“We’re still evaluating this,” Hemstrom said.
The Council has a web-based tool, here, that provides current Northern Pike suppression data, information on the treats the predator poses, and information about how the public can help keep pike from reaching anadromous waters below Chief Joseph Dam.
But the Columbia below Chief Joseph Dam also has what might prove to be a secret weapon against pike, he said: Stickleback, a carnivorous fish that don’t grow very large – about four inches long at best – but have a broad appetite that includes insects, small crustaceans, and fish larvae.
“Stickleback are predators on pike eggs, and we have gobs of stickleback,” Hemstrom said. “Even if pike could spawn in these areas, the sticklebacks would eat them, most likely.”
One complication of the pike suppression effort, potentially at least, is that there is no coordinated plan of attack if pike take hold downstream of Chief Joseph. Washington’s Invasive Species Council is working to change that by, for example, proposing the creation of a state emergency-response fund and facilitating the development of a plan for how to respond to the continued spread of Northern Pike.
“We need a plan as well as funding,” the Council’s executive coordinator, Justin Bush, said. “In terms of invasive species, Northern Pike is one of our highest priorities. “Some species, we know, would be more damaging to our infrastructure and natural resources, like zebra and quagga mussels, but they are not currently here.”
Zebra and quagga mussels form hard masses of finger nail-sized shells that can clog water intakes and other submerged structures such as equipment at dams. They have infested areas of the Midwest and Southwest, but so far not the Northwest.
Greer Meier, Science Program Manager for the Upper Columbia Salmon Recovery Board in Wenatchee, said the board is tracking and participating in pike-suppression forums, as well as staying in contact with the public utility districts as they watch for pike.
“Our Upper Columbia listed salmon and steelhead could face a major threat from these fish moving downstream and occupying the reservoir areas where juveniles are migrating and rearing,” she said.
Huge pike with 16" kokanee in its stomach
The Western Governors’ Association has identified Northern Pike as one of the top threats in the West and established the Biosecurity and Invasive Species Initiative to focus attention on the impacts that invasive animals, plants, pests, and pathogens have on ecosystems, forests, rangelands, watersheds, and infrastructure in the Western United States. Workshops on challenges and opportunities in addressing invasive species are planned, and the Initiative could help coordinate a rapid response or leverage federal funding in the future to fight the problem.
Elsewhere, the Coeur d’Alene Tribe of Indians also is working to eliminate Northern Pike from parts of Lake Coeur d’Alene, where the species was introduced illegally. In a letter to the region in August 2018, Caj Matheson, director of the Tribe’s Natural Resources Department, wrote that targeted suppression efforts to remove pike from Windy Bay to protect native Westslope Cutthroat Trout and Bull Trout have been promising and that the Tribe plans to expand suppression efforts beyond Windy Bay with a “large-scale suppression effort” in 2019.
Angelo Vitale, fisheries program manager for the Tribe, said there have been “some very positive responses to this early work,” adding, “the Tribe is committed to redoubling its effort to implement a large scale suppression strategy to bolster the production of culturally important species like westslope cutthroat trout and bull trout.”
He said the strategy is well aligned with the mission of the Tribes to promote the recovery of native fisheries for the benefit of future generations. It also seems to be well aligned with the interests of the angling community, he added.
“Notably, the responses by anglers to a 2017 survey indicated broad support for both native species conservation efforts as well as for management strategies that aim to reduce the negative impacts of Northern Pike on more desirable fisheries," Vitale said.