The Future of Hatcheries: Wild Broodstock Programs

Science indicates little impact on genetic structure and diversity caused by wild steelhead broodstock programs over extended periods. A study (Gow et al., 2011) of five rivers in British Columbia (BC) over a 58-year period showed negligible impact on genetics. According to the study, “No discernible impact of hatchery supplementation using native broodstock. Our temporal analysis of steelhead trout from five rivers in southwestern British Columbia that have been subject to hatchery supplementation using native broodstock found no evidence of genetic changes associated with the onset and continuation of supplementation, neither within individual populations nor in the relationships.” Further, according to the “A review of hatchery reform science in Washington State” completed in January, 2020, “...recent empirical RRS (relative reproductive success) research has highlighted that hatchery programs employing 100% natural origin broodstock can provide demographic conservation benefits while maintaining genetic diversity with minimal or no apparent genetic fitness loss.”

The two most common methods for catching natural origin fish for broodstock programs are angler capture programs and traps. Both methods have advantages and disadvantages with angler capture programs being popular and widely used. Scientific data suggests (Whitney et al., 2019) that angler capture programs can result in lower mortality rates than pro- grams reliant of trap captures.

Angler capture programs are popular, and experience shows that using proper handling techniques and appropriate equipment will not result in the loss of fish. Scientific data also shows a very low mortality rate for broodstock programs. A study (Whitney et al., 2019) of fish caught and retained for a broodstock program on the South Fork of Idaho’s Clearwater River showed, “...that neither the survival of adults to spawning nor the subsequent hatchery survival of their progeny was negatively influenced by fight time and air exposure time for hatchery steelhead caught by recreational anglers for use as broodstock.” The study showed an average pre- spawn survival rate of approximately 97% over a three-year period.

Several wild broodstock programs in Oregon rely on live spawn techniques. After spawning the fish are provided a brief recovery period in captivity before being released back into their natural environment. Evidence is mounting that there is a high survival rate of spawned fish and increasing examples of live spawned fish successfully negotiating a year in their natural environment and returning for subsequent spawning. This is true for programs on Oregon’s coast as well as inland tributaries of the Columbia River.

Yes. Broodstock programs designed to increase natural origin fish are often labeled “conservation hatchery programs.” A study (Berejikian et al., 2018) showed increased natural reproduction and genetic diversity after ending a steelhead conservation hatchery program. The 17 year before-after-control-impact experiment measured the effects of a captive rearing program for steelhead on a key indicator of natural spawner abundance (naturally produced nests or `redds'). The supplemented population exhibited a significant (2.6-fold) increase in redd abundance following supplementation. Four non-supplemented (control) populations monitored over the same 17-year period exhibited stable or decreasing trends in redd abundance.

Loss of essential habitat has long been viewed as the primary cause of wild salmon and steelhead declines. Recent science however, points to ocean conditions (Welch et al., 2020) as the most likely cause of coast wide declines in wild fish populations. Out of control predation is another major factor and a recent published study (Nelsen et al., 2019) concludes “wild chinook salmon productivity is negatively related to seal density and not related to hatchery releases in the Pacific Northwest.” Science shows wild broodstock programs either increase natural origin abundance or have no effect.

There is little question that broodstock pro- grams designed to increase harvest opportunities are successful. British Columbia (BC) has used broodstock programs for decades and their success has been scientifically documented (Gow et al., 2011). Broodstock programs are also being used successfully in Washington, Oregon and California to provide increases in the number of harvestable salmon and steelhead.

Anglers in search of salmon and steelhead will congregate where fish are abundant. Because increased popularity of rivers with successful broodstock programs some anglers and department employees have been critical of broodstock programs. To decrease angling pressure on rivers with high numbers of harvestable fish more wild broodstock programs need to be implemented to spread harvest opportunities and anglers. With few exceptions hatchery fish can be retained while natural-origin fish must be safely released, and increased angling pressure often correlates to higher handle rates of wild fish. A study by Idaho Fish and Wildlife employees (Chiaramonte et al., 2018) found, “results of nearly all previous salmonid studies suggest that the air exposure and fight times reported herein would result in little to no mortality for trout and salmon in freshwater.” This is consistent with other information that shows catch-and-release encounters using proper handling and release techniques result in very low mortality of released fish.

Yes. Cases of natural origin broodstock being used successfully to help recover salmon runs on the verge of extinction are increasing. One example used remnant wild Chinook in Johnson Creek, a tributary to Idaho’s Clearwater River, that initially relied on just five remain- ing spawning pair (10 fish). Initiated in 1998 the run remains self-sustaining today. A study (Hess et al. 2012) evaluated and substantiated the success and benefits of the program.

Absolutely not! Responsible stewards have an obligation to ensure that agencies protect and preserve wild fish habitat. Conscientious anglers have a duty to comply with all rules and regulations, especially those intended to protect and enhance natural-origin fish. And reasonable people need to recognize that the general trend for the availability of quality freshwater habitat is decided- ly in the downward direction due to inexorable pressure from human population growth (Lackey 2003), which in turn equates to increasing pressure on hatcheries to ensure abundant and healthy fisheries. Responsible hatchery programs utilizing wild broodstock, when possible, can help ensure hatchery reared fish do not compromise wild populations. Our forefathers didn’t know what they didn’t know. They quickly discovered hatcheries could produce large numbers of fish. Unfortunately, they didn’t fully understand the life cycle of anadromous fish or the potential impacts of simply focusing only on production. Today we have the benefit of science driven data to correct and direct how our hatcheries operate. As the data and science demonstrates wild broodstock programs are a good investment, and it is also shows now is the time to aggressively invest in research focused on further improving hatchery practices so that tomorrow’s hatcheries produce fish as close to natural-origin as possible.