BEYOND HARVEST
ALLOCATION
October 10,2012
Wild Salmon
Escapement Allocation:
There are major unresolved issues associated with the effort
to re-allocate harvest share and management on the Columbia River. Since most
wild salmon and steelhead in the lower Columbia River are threatened with
extinction and protected by the Endangered Species Act, the health of all wild
populations of salmon and steelhead and recovery of threatened populations
should be included in any harvest management changes. The effect of harvest, especially
non-selective harvest that takes wild salmonids, is to subtract spawners from
their natal watersheds and this can have negative demographic and ecological
consequences. All harvest has an impact,
even harvest that targets hatchery fish, for there is always an associated kill
of wild salmonids that are caught and released.
The only way to effectively manage harvest to protect and recover wild
salmon and steelhead in the lower Columbia River is to regulate harvest to set
tributary and specific escapement targets, and then regulate harvest to meet
those targets. There must be sufficient
monitoring to ensure the escapement targets are met.
Knudsen (2000) confirms the importance of having
conservation escapement requirement: “Both productivity and biodiversity depend
on sufficient escapement of spawners to fully utilize the available freshwater
habitat, fertilize the systems with carcasses, and optimize genetic
diversity.”
Even though there are
currently interim spawner goals recommended (HSRG 2000; NMFS 2002) they have
not been adopted as formal requirements.
The important question is this: Does harvest support recovery of
ESA-listed salmon and steelhead and protect all wild populations utilizing the lower
Columbia River for reproduction? That is
a key question to ask of any harvest allocation plan.
There are other issues that must also be addressed along
with a spawner allocation. They include
releasing hatchery fish in the spawning areas used by wild salmon and
steelhead; stray hatchery fish that breed with wild salmonids and compete with
them for available habitat and food resources in the tributaries, the main stem
Columbia and in the estuary, and the impact of stray hatchery fish on streams
near hatchery release sites in the lower Columbia River. Each of these issues can seriously compromise
the effectiveness of recovery actions for wild salmonids in lower Columbia
River tributaries.
It is important to not only resolve allocation of fish among
user groups, but in doing so, to make sure that wild salmon and steelhead
recovery is a benefit of any harvest allocation
agreement.
Harvest reallocation problems
have been around for over 100 years. It
is not something new. The history of harvest reallocation in Oregon and
Washington indicates that the expected benefits from salmon and steelhead
spawner escapement have not been accomplished.
Beginning in the 1930s through the 1950s there were several citizen
initiative petitions aimed at protecting salmon from excessive harvest. The states of Oregon and Washington, in
response to citizen promoted measures, eliminated fixed harvest gear like traps
and fishwheels. In 1948 the Fish
Commission of Oregon evaluated this change to determine whether what they
called the “dire” depletion of salmon in the Columbia River had been addressed
by increasing salmon spawner numbers.
Their conclusion was that the fisheries that continued to operate
legally in the river simply consumed more
fish and the spawning escapement did not increase (Johnson et al 1948).
Commercial netting in Oregon
bays was brought to an end by citizen action in order to rebuild depleted
salmon and steelhead populations (Cleaver 1951). What happened is that some
species (coho salmon) continued to be over harvested in other fisheries. These two examples have one thing in common;
that is, the state fish management agencies did not establish a spawner
requirement and the fisheries could not be adequately controlled.
Harvest management involves two
primary activities: setting the allowable harvest and allocating the allowable harvest
among the different sport and commercial fisheries. The former is a technical
task, the latter is a political task. Too often the technical and the political
tasks are so intertwined that their separate roles become confused. To avoid that confusion the two activities
should be clearly separated
(separate oversight and
supervision paths) within the organization structure of the management agencies
(Lichatowich and Bakke 2012).
The questions in this harvest allocation agreement are
whether the agreement includes a spawner escapement requirement sufficient to
aid in recovery and reduce the impact of hatchery fish on the spawning grounds.
If the answer to either of those questions is “no”, then the allocation
agreement will be insufficient to meet Governor Kitzhaber’s dual goals of
increasing the economic benefits of the fisheries while aiding in the
restoration of threatened and endangered wild fish populations.
Reducing Impact of
Hatchery Salmon:
Governor Kitzhaber has expressed concern about the number of
hatchery fish in rivers. Naturally
spawning hatchery fish can and do interbreed with wild salmon in rivers reducing
the reproductive success of wild salmon (Araki et al 2009; Christie et al.
2011; Chilcote et al. 2010), most of which are threatened with extinction. In addition, naturally spawning hatchery fish
produce juveniles that compete with wild salmon for habitat and food, limit
nutrient enrichment of streams from salmon carcasses, and reduce the productive
capacity of rivers (Kostow et al. 2006).
In order to control the impact of naturally spawning
hatchery fish in Columbia River tributaries two actions are needed: 1) remove
production releases from the tributaries and move them to off-channel net pens
in the Columbia River; 2) control stray hatchery fish entering tributaries to
help reduce spawning with wild salmonids and creating competition for habitat
and food. These two actions will assist
in recovery of ESA-listed salmonids in the tributaries. The species that are now released into the
tributaries and causing problems are hatchery winter and summer steelhead, coho
salmon and spring chinook. By moving
production releases of coho and spring chinook to off-channel net pens and
applying measures to control strays in streams near those net pens, wild coho
and spring chinook in the tributaries could benefit. It is important to avoid transferring the
upstream impacts to downstream locations. Monitoring and evaluation is
necessary to prove exactly what benefits are achieved in the tributaries.
In addition, releases of hatchery salmon at net pens or in
tributaries have an impact on wild salmon and steelhead in the mainstem
Columbia, the estuary and near-shore ocean waters. These impacts include competition for food
and habitat, predation and predator attraction.
These issues will not be resolved by moving production hatchery fish to
net pens.
Impacts of hatchery steelhead on wild steelhead in
tributaries will have to be addressed at the tributary level, for these fish
are not a target species for the commercial fishery and should not be moved to
off-channel net pens. However,
converting the fishery to selective gear for hatchery fish and live release of
wild fish would contribute to improved spawner escapement in the tributaries
and increase nutrient enrichment.
Recommended
Hatchery Salmon to be Relocated:
Sandy River spring chinook and coho salmon
Molalla River spring chinook salmon
North Santiam spring chinook
Clackamas River spring chinook and coho salmon
Bill Bakke, Conservation Science Director, Native Fish
Society
References
Araki,
Hitoshi, Becky Cooper, and Michael S. Blouin. 2009. Carry-over effects of
captive breeding reduces reproductive fitness of wild-born descendants in the
wild. Biological Letters 5: (5) 621-624.
Chilcote,
Mark M.W., K.W. Goodson, and M.R. Falcy. 2010. Reduced recruitment performance
in natural populations of anadromous salmonids associated with hatchery-reared
fish. Can. J. Fish. Aquat. Sci. 68:
511-522.
Christie,
Mark R., Melanie L. Marine, Rod A. French, and Michael S. Blouin. 2011. Genetic
adaptation to captivity can occur in a single generation. Proceedings of the
National Academy of Sciences of North America (PNAS)
Cleaver, F.C. 1951.
Fisheries statistics of Oregon. Oregon Fish Commission. Contribution No. 16.
Hatchery Science Review
Group (HSRG). 2000. Findings of the Columbia River System-wide Report. HSRG
Report Appendix E.
Johnson, D.R., W.M.
Chapman, and R.W. Schoning. 1948. The effects on salmon populations of the
partial elimination of fixed fishing gear on the Columbia River in 1935. Fish
Commission of Oregon.
Knudsen, et al. 2000.
Sustainable fisheries management: Pacific salmon. Eds. E. Erich Knudsen,
Cleveland R. Steward, Donald D. McDonald, Jack E. Williams, and Dudley W.
Reiser. Lewis Publishers. Ann Arbor
Press.
Kostow, Kathryn E. and
Shijie Zhou. 2006. The effect of an introduced summer steelhead hatchery stock on the productivity of a wild winter
steelhead population. Transactions of the American Fisheries Society
135:825-841.
Lichatowich and Bakke.
2012. The way forward to protect and recovery wild fish. The Osprey. Issue No.
73.
National Marine Fisheries
Service. April 4, 2002. Interim abundance targets for interior Columbia Basin
salmon and steelhead listed under the Endangered Species Act (ESA). Bob Lohn
letter to Frank L. Cassidy, Jr, Chairman, Northwest Power Planning Council.
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