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NW Fishletter #222, October 31, 2006
[2] Success Of Updated Hatchery Programs Still Unproven By relying on salmon hatcheries to boost natural runs, including some listed under the Endangered Species Act, the region may be putting all its fish eggs in one basket, according to two recent peer-reviewed articles, whose authors say the jury's still out regarding potential benefits from the hatchery supplementation effort. Supplementation uses local wild brood stock that are crossed with other wild fish. The progeny are raised in a hatchery for a time, and then usually out-planted in acclimation ponds where the young fish are allowed to migrate voluntarily. It's a strategy implemented in more than one-third of all Northwest hatchery programs. One study (Araki et al.) in press at the journal Conservation Biology reports that a steelhead supplementation program in the Hood River gave a single-generation population boost to the natural steelhead numbers without "obvious" genetic consequences. However, the researchers said supplementation "should probably not be relied on as a permanent solution to dwindling natural populations," and that the offspring of breeding between hatchery fish (either traditionally raised or by supplementation) were less fit than researchers expected. "The long-term effects of supplementation remain untested," said the study, though the authors estimated each wild female taken into the hatchery for spawning generated four to 10 times as many wild-born adults as a female spawning in the wild does. Wild fish advocate Bill Bakke, executive director of the Portland-based Native Fish Society, didn't agree with the findings of the Hood River study. "A closer examination of the data shows a decline in the fitness of hatchery fish," he told NW Fishletter. Another article comparing hatchery and wild spring chinook says the results for the Yakima River are so far unclear, but changes observed in migration timing and fecundity in supplemented fish may reduce the overall fitness of the stock. The article (Knudsen et al.), published in the July 2006 Transactions of the American Fisheries Society, reported that "the most important observation to be derived from this study is that hatcheries do not produce fish that are identical to wild fish, even in a program designed to minimize the differences between the two production types." The study went on to say that, "the implications for population productivity need to be better understood as we proceed with the use of conservation hatcheries to sustain salmon and steelhead populations." But that hasn't stopped other high-level hatchery reviews, patterned after a big effort to reform Puget Sound hatcheries, from recommending the practice. The U.S. Fish and Wildlife Service is using the methodology developed in the Sound study to review operations at all 21 of its facilities in the Columbia River Basin. In announcing the draft results of a review of its Leavenworth hatchery complex in the upper Columbia, the USFWS review team is calling for some big changes. These include phasing out the Carson stock--a mixed stock of Snake and Columbia spring chinook trapped at Bonneville Dam in the 1950s and 1960s--in favor of using a native spring brood stock that is "integrated genetically" with a Wenatchee River ESA-recovery hatchery brood stock. The initial review concluded that the spring chinook program at the Leavenworth Hatchery, which was built to mitigate effects of Grand Coulee Dam, is the only one of four programs that provides "significant" fisheries benefits to the Yakama Nation and recreational fishers in the mid-Columbia region, principally in the Icicle Creek region. It should be a "very" high priority, the initial review said. The facility produces several thousand chinook for tribal harvest every year, and several thousand more for recreational fishers. The review team also recommended ending the spring chinook program at the Entiat Hatchery because it provides few fishery benefits, while an integrated summer chinook program would boost fish numbers in the Entiat River and mid-Columbia for both tribal and non-tribal fisheries. The review also said the Entiat hatchery could help recover spring chinook in the region, a role also suggested for the Winthrop Hatchery on the Methow River. The Winthrop facility offers "significant potential" to reach both conservation and fishery goals for ESA-listed spring chinook and steelhead, according to the review. However, it won't work unless better ways are developed to trap natural-origin spring chinook adults for brood stock, monitor escapement of hatchery-origin chinook, and remove excess hatchery-origin steelhead from any supplementation effort in the Methow. Another huge hatchery review, which will also look at harvest issues, has begun under the lead of NOAA Fisheries and facilitator Jim Waldo. This ambitious plan was kick-started to life last January by Jim Connaughton, chair of the White House Council on Environmental Quality. Addressing a salmon conference in Portland, Connaughton said the feds would scrutinize 180-odd hatchery programs in the Columbia Basin, closing those not contributing to the recovery of wild stocks, and maintaining others only if they didn't allow large numbers of ESA-listed fish to be caught incidentally. In an Oct. 11 progress report, Waldo's group said it had completed a pilot review of hatcheries in the lower Columbia, a region with 40 different salmon and steelhead populations, and found risks could likely be reduced and benefits increased by "resizing" hatchery programs and improving brood-stock management, along with upgrading facilities. Since hatchery fish can sustain higher levels of harvest than wild stocks, the group said this "will both reduce the potential adverse effects of too many hatchery fish on the spawning grounds and increase the value of hatchery production to fisheries." The pilot review also recommended a brood-stock integration strategy that would meet both harvest goals and watershed-level recovery needs, but added that programs must be developed to identify both natural and hatchery-origin fish on spawning grounds or at the hatchery. It said "segregated" hatchery programs, where fish are raised primarily to satisfy harvest obligations, should make sure all such fish are identified to keep less than 5 percent of them from reaching wild spawning areas, and suggested weirs, racks or other means of selective harvest be developed to keep excess hatchery fish from reaching spawning grounds. The pilot review said one of the biggest management challenges would be to convert these "segregated" programs to "integrated" ones, in which fish would be raised in hatcheries to add to wild-fish abundance. The review said "current 'integrated' programs' are not properly integrated." Both hatchery reviews will used a tool developed in the Puget Sound analyses by consultant Lars Mobrand called the 'All-H Analyzer,' referring to 'hatcheries, harvest, hydro, and hatcheries.' The tool was designed to keep track of assumptions and predict effects of conservation and fisheries as they change. But critics of the All-H methodology say it relies more on professional opinion than the best available science, especially since the All-H tool includes a factor that estimates the effectiveness of hatchery fish spawning in the wild--where data is especially sparse. Supporters of the model say the tool allows managers to explore the implications of alternative management of the different H's, and make informed decisions on how best to balance their effects. However, wild fish advocate Bakke says that although regional policymakers may change terms like "supplementation" for "integration," the problem is still the same. "These hatcheries will lead to the extinction of wild fish. They can increase production, but they can't increase productivity." -B. R. The following links were mentioned in this story:
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