Hatchery Reform in Washington State

Abstract

Hatcheries support nearly all major fisheries for Pacific salmon (Oncorhynchus spp.) and steel‐head (anadromous O. mykiss) in the Pacific Northwest. However, hatcheries have been a major source of controversy for over 30 years. The Hatchery Scientific Review Group (HSRG) was tasked by Congress to identify solutions to well‐known problems so hatcheries could better meet their goals of supporting sustainable fisheries and assisting with the conservation of natural populations. We reviewed over 100 facilities and 200 programs and identified three principles of hatchery reform: (1) goals for each program must be explicitly stated in terms of desired benefits and purposes; (2) programs must be scientifically defensible; and (3) hatchery programs must respond adaptively to new information. We also identified several emerging issues critical to the success of hatcheries. We concluded that hatcheries must operate in new modes with increased scientific oversight and that they cannot meet their goals without healthy habitats and self‐sustaining, naturally‐spawning populations.

Straying of hatchery salmon in Prince William Sound, Alaska

“…The amount of straying that a wild population can tolerate is uncertain. The guiding management plan for hatcheries in PWS suggests an upper limit of hatchery strays of 2% (PWS CRRPT 1994), while other studies suggest that thresholds as high as 5% or 10% may be detrimental to wild salmon populations through mechanisms discussed above (Ford 2002;Mobrand et al 2005). In our study, we found a wide range of straying proportions across years, but hatchery pink, chum, and sockeye salmon exceeded all proposed thresholds of straying into many wild salmon spawning locations.…”

“…The straying of hatcheryreared salmon, on the other hand, may be disruptive to wild populations. A few generations of artificial breeding and rearing of salmon in a protected environment can lead to domestication, altered gene frequencies, and phenotypic changes that reduce the adaptive fitness of hatchery salmon (Fleming and Gross 1993;Berejikian et al 2001;Myers et al 2004;Mobrand et al 2005;Araki et al 2007;Naish et al 2007;Araki et al 2008;Grant 2012). Hence, hybridizations between hatchery and wild fish may also decrease the adaptive fitness of wild populations (McClelland et al 2005;Ford et al 2006;Wessel et al 2006).…”

“…Based on reported straying of less than 2.2% for pink salmon (Boyd 1964;Blair 1968), the PWS Comprehensive Salmon Management Plan (PWS CRRPT 1994) sets a limit on the proportion of hatchery fish in PWS streams at 2%. From a genetic perspective, additional threshold percentages of hatchery strays in wild spawning systems have been suggested, including less than 5% (Mobrand et al 2005). Additionally, a quantitative genetics model by Ford (2002) indicated that over a wide range of model parameters, exceeding 10% hatchery strays with introgression into a wild stock may produce a significant loss of fitness.…”

Breeding success of four male life history types of spring Chinook Salmon spawning in an artificial stream

“…Concerns about how supplementation may change the genetic composition of salmonid populations prompted Mobrand et al (2005) to propose that the proportion of natural-origin fish on spawning grounds and in hatchery broodstocks should always be greater than the corresponding proportion of hatchery fish. This protocol dilutes potential domestication because fifty percent or more of the genes transmitted from one generation to the next by hatchery fish are subjected to natural selection pressures (Mobrand et al 2005).…”

Species Composition and Relative Abundance of Large Medusae in Puget Sound, Washington

“…Skagit Bay (northern) and Nisqually Reach (southern) are two of the most biologically different areas but are among the least urbanized estuaries in Puget Sound. However, human activity may play a role in several interacting ways: (1) locally, such as through nutrient loading, shoreline (Shipman et al 2010) and substrate hardening, and manipulation of the pelagic fish fauna by hatchery supplementation (Mobrand et al 2005) and fishery harvests (sport, commercial, and subsistence); and (2) globally, such as through species introductions (Cohen 1998;Mills et al 2000;Cohen et al 2001) or influences on climate that affect physical forcing and nutrient delivery from the Pacific Ocean or surrounding watersheds (Snover et al 2005;Moore et al 2008). Efforts to understand the myriad effects of human activity and their interactions on the pelagic ecosystem in Puget Sound have been negligible.…”