are an effective tool for rebuilding spring chinook abundance and productivity
in the Yakima Basin without impacting wild fish, according to a recent study
published in the
American Journal of Aquaculture.
study, based on 33 years of planning and research, found that the Cle Elum
Supplementation and Research Facility increased fish spawning in the Yakima
Basin while unsupplemented populations continued to struggle.
Cle Elum facility in the Yakima River basin is an integrated spring chinook salmon
hatchery program designed to test whether artificial propagation can increase
natural production and harvest opportunities while keeping ecological and
genetic impacts within acceptable limits.
natural-origin (naturally spawned) fish are used for hatchery broodstock.
incubation, and early rearing occur at a central facility; presmolts are
transferred for final rearing, acclimation, and volitional release at sites
adjacent to natural spawning areas, where returning adults can spawn with
first wild broodstock were collected in 1997, and age-4 adults have returned to
the Yakima River since 2001.
unsupplemented population in the adjacent Naches River watershed provides a
reference for evaluating environmental influences. The program has been
comprehensively monitored from its inception.
study’s synthesis of findings, many already published, is as follows:
supplementation increased the harvest, redd counts, and spatial distribution of
natural-origin returns were maintained;
straying to nontarget systems was negligible;
natural-origin females had slightly higher breeding success (production of
surviving fry) in an artificial spawning channel, while the behavior and
breeding success of natural- and hatchery-origin males were similar;
hatchery-origin fish showed differences in morphometric and life history
high rates of hatchery age-2 (minijack) production were reported, but the
observed proportions of out-migrating juvenile and adult (ages 4 and 5)
returning males were comparable for hatchery- and natural-origin fish;
hatchery smolts did not affect the levels of pathogens in natural smolts;
the ecological interactions attributed
to the program were within adopted guidelines.
study is required to assess the long-term impacts on natural production and
productivity,” says the study.
Synthesis of Findings from an Integrated Hatchery Program after Three
Generations of Spawning in the Natural Environment” can be found in the North
American Journal of Aquaculture at http://afs.tandfonline.com/doi/full/10.1080/15222055.2015.1024360#abstract
Cle Elum study results refute commonly held beliefs that hatcheries hinder
naturally returning populations and that natural-origin populations will
rebuild in highly altered river systems in the absence of hatchery programs,”
stated a press release about the study issued by the Columbia River
Inter-Tribal Fish Commission.
research found that salmon redds increased in the Upper Yakima River by 120
percent with supplementation, while the number of redds increased 47 percent in
the unsupplemented Naches River. During the same time frame, natural-origin
returns in the Upper Yakima River increased 14 percent with supplementation
while natural-origin returns in the unsupplemented Naches River decreased by 12
percent. No pathogens or disease interactions between natural-origin and
hatchery origin populations were detected and ecological interactions were
largely neutral,” noted CRITFC.
“Our results demonstrate that natural spring chinook
populations were maintained or increased in the supplemented Upper Yakima
River, while the adjacent unsupplemented population in the Naches River
continues a slow but steady decline”, said Dave Fast, Senior Research Scientist
for the Yakama Nation Fisheries program and lead author of the publication.
“Habitat restoration is occurring in both subbasins and these results indicate
that we cannot rely on habitat restoration alone to achieve recovery. We need both continued supplementation and
expansion of habitat restoration actions to keep pace with the ever-increasing
threats these fish face for their survival.”
Cle Elum Spring Chinook Supplementation and Research Facility was conceived in
the 1980s as a harvest mitigation program.
By the 1990s, that goal was broadened to a hatchery supplementation program
that would increase harvest opportunities, increase natural spawning on the
spawning grounds, and provide research that could address critical issues in
resurgence of spring chinook in the Yakima Basin has substantially increased
fishing opportunities after a 40-year absence, significantly improved
relationships, and increased opportunities for partnerships,” said CRITFC.
innovative project began as a dream of our elders to return fish runs that were
damaged. While many criticize tribal supplementation efforts, failure to
increase fish populations is not an option.
Our current situation requires us to act for the survival of our fish as
well as the survival and well-being of our tribal communities, tribal culture,
and our traditional foods,” Sam Jim Sr., chair of the Yakama Tribal Council’s
Fish and Wildlife Committee, has said of the program.
American Fisheries Society is offering free access to the paper through August
31, 2015. The paper can be downloaded
Portland-based Columbia River Inter-Tribal Fish Commission is the technical
support and coordinating agency for fishery management policies of four
Columbia River Basin treaty tribes: the Confederated Tribes of the Umatilla
Indian Reservation, the Confederated Tribes of the Warm Springs Reservation of
Oregon, the Confederated Tribes and Bands of the Yakama Nation and the Nez