number and size of northern pike found in Lake Roosevelt, the reservoir backed
up behind Grand Coulee Dam, is growing and so too is the determination of
tribes and the state of Washington to eradicate the voracious and invasive
species, but they may be running out of the funds needed to continue their
pike are a threat to nearly every species they encounter. Predation by pike on
smaller fish imperils efforts to raise and release trout, kokanee, and other
game fish into the lake. If they continue to proliferate in Lake Roosevelt.,
they could eventually find their way downstream beyond the dam and into the
Columbia River where they could threaten populations of threatened and
endangered salmon and steelhead.
if they can be contained in the lake, but not eradicated, they could eventually
threaten anadromous fish that tribes hope to reintroduce upstream of Chief
Joseph and Grand Coulee dams. A habitat assessment by the Spokane Tribe of
Indians, partly paid for by the Northwest Power and Conservation Council and
Bonneville Power Administration cost-savings funds, is underway. The $200,000
study is assessing whether reintroducing salmon and steelhead into waters
upstream of Grand Coulee Dam is feasible as it researches the potential habitat
available to support spawning and juvenile rearing.
CBB, April 15, 2016, “Council Votes To Move Forward On Salmon/Steelhead Habitat
Assessment Above Grand Coulee,” http://www.cbbulletin.com/436490.aspx)
the proliferation of larger northern pike could threaten that and the funds to
continue eradicating the invasive species is uncertain, said Laura Robinson,
program implementation and liaison specialist with the Council’s Fish and
Wildlife staff, at the Fish and Wildlife Committee meeting in Missoula Tuesday,
year, during a 16-week season, 114 adults were caught,” she said in a follow-up
email. “This year, in the 6.5 weeks they have been netting so far, 702 adults
have been caught. All in the Kettle Falls area.”
to study and eradicate the species from the lake began last summer. Researchers
from the Washington Department of Fish and Wildlife, the Spokane Tribe of
Indians, the Kalispel Tribes and the Confederated Tribes of the Colville
Indians have been out gillnetting to reduce the northern pike population in the
gillnetting is also part of a long-term study to keep track of the number and
locations of pike in the lake.
CCT, Kalispel, and WDFW are all working on the eradication work,” Robinson
said. “At this point we are unsure about funds and the extent of the work they
will be able to do this year.”
had offered a quick update at the Fish and Wildlife meeting to “signal the
problem for them and give them a heads up that we may hear more about funding
needs for it in the future. There will be a presentation to the Council in July
on the work being done.” That presentation will be headed up by Washington
Council member Guy Norman.
biologists caught a 20-pound female who had gorged on smaller fish. Her gonads,
which were full of eggs, weighed in at 2.2 pounds, according to a blog called
“Nightmare Fish” by John Harrison on the Council’s website (https://www.nwcouncil.org/news/blog/northern-pike-update-march-2017/).
eat crayfish. They eat suckers. They eat bass, trout, Walleye, Perch, Lake
Whitefish, juvenile White Sturgeon, mice, and baby ducks. They even eat their
own young,” Harrison wrote.
eat everything,” said Holly McLellan, principal fish biologist for the Colville
Confederated Tribes. “We need to stop pike from moving downstream now.”
pike in Lake Roosevelt likely migrated down the Pend Oreille River, which
enters the Columbia just north of the international border. The Kalispel Tribe
and WDFW have been aggressively removing pike in the Pend Oreille River since
2007 and have been successful in Box Canyon Reservoir. They are now focusing
their efforts in Boundary Reservoir, all in an effort to stop the downstream
spread of this invasive species, Harrison wrote.
recently visited Lake Roosevelt and spoke with Colville and Spokane tribe
biologists as they netted pike.
was amazed by the number of adult pike they were catching with so little
effort,” Norman said in Harrison’s blog. “It certainly rang the alarm bells for
me. This is something that could have significant ecological effects on the
lake, and on fisheries both in the lake and downriver. We need to get on top of
improve understanding of the population in Lake Roosevelt, every other week
this year since February, biologists with WDFW and the tribes have been netting
pike in the shoreline shallows around the Colville and Kettle rivers, where the
fish school in preparation for spawning in May and early June. It’s part of an
effort that began last year, even though the first pike was discovered in the
lake in 2009.
addition to Council support last year for pike eradication, the Colville Tribes
have been funding suppression efforts through their Columbia River Fish Accord
with BPA and with internal tribal funds.
is no doubt pike numbers are higher this spring than during the same period
last year, McLellan said.
mid-March, 326 were caught ranging in size from 12 to 42 inches and averaging
17 inches and 2 pounds per fish, or about 10 times more than were caught during
the same period in 2016.
research fishing will continue through early June when spawning will be over
and the fish will move into deeper water, according to the blog. Next fall,
researchers will electro-fish and gillnet the shorelines, as they have in
recent years, to assess and remove the population of juvenile pike.
the Colville Tribe and WDFW have established monitoring stations downriver in
Lake Roosevelt, in Lake Rufus Woods behind Chief Joseph Dam, in the Okanagan River,
and in Banks Lake, the reservoir above Grand Coulee that supplies irrigation
water to the 600,000-acre Columbia Basin Project. Water samples will be tested
for pike DNA that would serve as an early warning that the predators, even a
small number of them, are present so that eradication efforts could begin
population will keep expanding if we are not aggressive enough with the
removal,” McLellan concluded.
September 23, 2016, “Council OKs More Funds For Fighting Pike Invasion: ‘Pike
Pose Enormous Threat To Salmon, Steelhead,” http://www.cbbulletin.com/437602.aspx
May 20, 2016, “Considering Predation Levels When Reintroducing Salmonids Above
High Head Dams,” http://www.cbbulletin.com/436761.aspx
March 11, 2016, “Council FW Committee Moves Forward On Salmon Reintroduction
Study Above Grand Coulee,” http://www.cbbulletin.com/436211.aspx
CBB, January 15, 2016, “Council Considers More Money For Pike Removal: ‘An
Alarming Increase In Pike Abundance,” http://www.cbbulletin.com/435860.aspx
CBB, December 18, 2015, “Council Moves Proposal For Evaluating Salmon Habitat
Above Grand Coulee To Science Review,” http://www.cbbulletin.com/435731.aspx
CBB, Nov. 19, 2015, “A Northern Pike Caught In John Day Reservoir: For Salmon,
Canary In The Coal Mine?” http://www.cbbulletin.com/435580.aspx
CBB, October 16, 2015, “Can Salmon, Steelhead Survive Above Grand Coulee Dam?
Council Investigation May Provide Answer,” http://www.cbbulletin.com/435273.aspx
CBB, September 18, 2015, “Council Moves Ahead With Plan To Assess Potential
Salmon Habitat Blocked By Grand Coulee,” http://www.cbbulletin.com/435022.aspx
CBB, July 17, 2015, “Invasive Northern Pike Spreading Further, Reproducing;
Council Hears Information On States’ Policies,” http://www.cbbulletin.com/434535.aspx
CBB, Jan. 16, 2015, “Tribes Lay Out Process For Investigating Feasibility Of
Salmon Reintroduction Above Grand Coulee Dam” http://www.cbbulletin.com/432935.aspx