Supplemental funding for a northern pike suppression project
managed by the Spokane Tribe of Indians was approved by the Northwest Power and
Conservation Council at its February meeting, but on the condition that the
Independent Scientific Review Panel review the Tribe’s latest proposal.
In March, the ISRP completed that review and gave the Lake
Roosevelt Northern Pike Suppression Plan supplemental proposal its approval,
saying it largely meets scientific review criteria.
However, it also put conditions on the proposal, most of
which had to do with final reporting of the project.
The ISRP review of the supplemental project, submitted to
the Council March 28 (http://www.nwcouncil.org/fw/isrp/isrp2016-6/), followed
on a previous review completed by the ISRP in January
The supplemental proposal is to help the Spokane Tribes
remove invasive pike from Lake Roosevelt. Initially, the request from the
Tribes was for $71,211 in order to provide additional gillnetting of the
invasive fish through March. However, the Council, following the recommendation
of the Bonneville Power Administration, funded the supplemental proposal for
$8,507 using Budget Oversight Group funds.
The request is in addition to a project already funded by
BPA at a cost of $1,314,199 during fiscal year 2016.
Managers of Lake Roosevelt fisheries are concerned about the
quick spread of the fish throughout the lake and ultimately into the
mid-Columbia River. A survey of Lake Roosevelt in 2015 found “an alarming
increase in Pike abundance.” At the same the 2015 spring angler catch rates
increased significantly, with anglers routinely catching pike in the shallow
bays in the Columbia River near Kettle Falls and on the Kettle River.
They are especially concerned about the spread of the
predator to the Spokane and Sanpoil rivers where native redband trout
populations are already hindered by non-native walleye, according to the
“In addition, Pike pose an enormous threat to salmon and
steelhead recovery efforts below Chief Joseph Dam on the Columbia River,”
according to the request.
The Council also had agreed to fund the project in June 2015
for $28,531, deeming the request “urgent.” However, the second year of funding
was conditioned on a favorable review of the project by the ISRP. A pike
suppression plan was submitted to the ISRP for review and ISRP completed its
work January 25, 2016, but asked the Tribe for a response on eight issues.
Among those issues, the ISRP found that they needed:
--clearly defined hypotheses about several northern pike
--additional detail and information regarding methods being
--time deliverable objectives.
In order to keep the suppression effort moving along until
the science review is complete, which it now is, they asked for funding that
would continue the gillnetting effort in March.
Northern pike are voracious predators that are a likely threat
to native species and non-native game fishes and they could potentially move
downstream in the Columbia River and possibly impact the recovery of ESA listed
salmon, according to Council information. The project proponents contend that
“it is critical that a monitoring and suppression plan be developed immediately
while abundance is still relatively low… to reduce the risk of Northern Pike
numbers expanding within Lake Roosevelt and beyond.”
The proposed project is closely related to work by the Kalispel
Tribe in the Box Canyon Reservoir in the Pend Oreille Subbasin. The ISRP
concluded that the Kalispel Tribe’s effort to suppress the Northern pike
population in Box Canyon Reservoir was justified. In that project, the Kalispel
Tribe is applying similar gillnetting techniques to target spawning populations
in shallow water.
The ISRP identified six qualifications that it said can be
addressed when finalizing the statement of work for the Council and Bonneville
Power Administration. They include:
1-Include explicit hypotheses to be tested by the proposed
activities and provide quantitative objectives for what is to be achieved.
2-Include quantitative objectives for the northern pike
suppression effort as a means to evaluate program success (e.g., reduce
northern pike CPUE by __ percent and reduce the relative abundance of large
northern pike [> __ mm total length] by __ percent by the year 20___).
Quantitative objectives should be developed for each metric used to evaluate
northern pike suppression, and a time frame should also be included in each
3-Include quantitative objectives regarding the protection
of native fishes captured as bycatch.
4-Revisit the elements of proposal that describe criteria
for assessing the effects of bycatch and actions to alleviate the effects of
bycatch on native species. The focus should be on preventing population-level
effects of bycatch on native species. We question bycatch limitations for
non-native piscivorous fishes (e.g., walleye) as they do not appear to be
consistent with the Council’s Fish and Wildlife Program to protect native
5-The planned use of 4-hour gillnet sets during daylight
hours using nets with panels of five different mesh sizes needs to be
supported. A detailed review of literature or a comparative study of catch
rates during the day and at night, for varying durations of gillnet sets, and
for different mesh sizes is needed to determine the design of gillnets and sets
that will optimize catch efficiency for northern pike.
6-Include a study design and description of the otolith
microchemistry methods the project will use to determine the natal origins of
northern pike sampled in Lake Roosevelt. Discuss how knowledge of natal origins
will inform adaptive management decisions regarding northern pike suppression
in Lake Roosevelt.
-- CBB, January 15, 2016, “Council Considers More Money For
Pike Removal: ‘An Alarming Increase In Pike
-- 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, July 17, 2015, “Invasive Northern Pike Spreading
Further, Reproducing; Council Hears Information On States’ Policies,” http://www.cbbulletin.com/434535.aspx