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Since the listing of Columbia River chum salmon as an Endangered Species Act "Threatened"
species in March of 1999, WDFW, the U. S. Fish and Wildlife Service, and a variety of local
citizen groups have started the process of recovering these fish. While achieving full recovery
will necessarily be a long term process, the following discussion outlines projects that are
underway and identifies some future needs.
- Genetic Diversity - Genetic samples have been collected from 50 or more fish each from
Hamilton Creek, Hardy Creek, and Grays River. Electrophoretic analysis has been completed
for the Grays River and Hamilton Creek Populations. WDFW has collected a few samples
from other areas, when the opportunity allows. However, few samples are collected with the
few observed fish and the present funding levels.
- Spawning Channels - WDFW created spawning channels in Hamilton and Gorley Creek in
the 1980's. The Hamilton spring spawning channel was modified in 1997. The U.S. Fish and
Wildlife Service is 2/3 complete on a spawning channel on Hardy Creek. If funds can be
secured (about $40,000), the channel will be completed in the fall of 2000.
WDFW and partners have requested funding to establish a spawning channel in Duncan
Creek. This area historically supported chum salmon and has the spring flow that should
make this project successful. After the construction of a lake in the lower end of Duncan
Creek that created passage and other habitat problems, the local, self-sustaining population
crashed.
- Hatchery Supplementation - WDFW initiated the development of a local broodstock of chum
salmon on the Grays River in 1998. The purpose of this program was to reduce extinction risk
in the event of a natural disaster and to develop a broodstock for rebuilding of local chum
population. A portion of progeny are released on station with the remaining released at
Chinook River hatchery for a Chinook River rebuilding program.
- Habitat Assessment - WDFW is working on a cooperative study to perform a habitat
analysis for chum salmon in most Lower Columbia River tributaries. One goal of this analysis
is to prioritize habitat actions needed to recover chum salmon.
Determine the within region genetic diversity of chum salmon.
- Collect additional genetic samples from spawning populations in the Columbia River.
Presently, WDFW and USFWS have proposed that the Bonneville trap should be
operated through December to facilitate non-lethal genetic sampling from the above
Bonneville population.
- WDFW personnel will continue to collect genetic samples when conducting fall stream
surveys. However, the small population sizes and current funding limits this effort.
Develop an accurate population estimate for Grays River, and Hamilton and Hardy Creeks.
- WDFW has a long-term data from these basins. The data consists of live and dead
counts conducted through the spawning season. In addition, WDFW has used carcass
tagging to develop population estimates in some years. WDFW is in the process of
analyzing this data using a variety of population estimation methods.
Develop spawner/recruit curves for chum populations.
- Once population estimates are finalized, WDFW will proceed with the development of
spawner/recruit analysis.
Lessen extinction the near term risks to chum population through habitat modification and/or
hatchery intervention.
- With only two confirmed self-sustaining population centers, there is some risk that a
catastrophic event or events may further increase risks to lower Columbia River chum
salmon. By establishing more self-sustaining populations this type of risk will be
reduced. Also, there is substantial disconnectivity between population centers making
colonization between these centers less likely. If self-sustaining populations cannot be
maintained in the current habitat, near term actions can include modifying habitat that
can support chum salmon and/or maintaining hatchery broodstocks until habitat can
support chum salmon.
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