The Coast Range Association Salmon & Survival Why Native and Hatchery Salmon are Different

INTRODUCTION

For the last 125 years, hatcheries have been used to increase production of salmon for fisheries. In the 1940s, they were drafted into service to mitigate for the development of federal and private dams that blocked salmon access to their spawning grounds. They have been used as a mitigation for habitat destruction for more than 60 years.

In the 1930s, scientists recognized that salmon returned to the rivers of their birth. The home stream theory was developed based on information from tagging studies. The home stream theory held that the best way to maintain the salmon runs was to protect the salmon population in each watershed. This conservation concept was based on two integrated factors: the native wild salmon in a watershed and the salmon habitat in that watershed. This scientific understanding was abandoned as the Northwest moved into the dam building era stretching from the 1930s through the 1970s in the Columbia River Basin. The hatchery was selected as the best way to maintain the salmon runs even though there was no scientific basis for this belief. It became the politically acceptable way to develop watersheds and have a salmon fishery. The hatchery was never designed to be an ecological tool to maintain the salmon runs; it was used merely to replace wild salmon and their watersheds with fish to catch.

The purpose of the Endangered Species Act (ESA) is to recover locally adapted native wild salmon in their natural habitats. Advances in the scientific understanding of salmon confirmed the fact that salmon are the result of local adaptation. The hatchery concept was forced to change. The new hatchery concept is called by various names: the conservation hatchery, native broodstock hatchery and supplementation hatchery. This new configuration of the hatchery is based on the premise that the hatchery can be used to rebuild wild runs of salmon in a watershed.

The idea of the conservation type hatchery has broad social and political appeal, it just lacks biological credibility. Further, its premise is wrong, because hatcheries are still intended to function as a replacement for wild salmon and habitat. With the flawed notion of depending on hatcheries rather than rivers to ensure continued fish runs, there is no social or institutional commitment to maintain native, wild salmonids and the habitats that support them.

In recent years, agencies, politicians and harvesters have latched onto the notion of using hatcheries for conservation. In cases where so few individual salmonids survive that only extreme measures will prevent the line from winking out of existence, conservation hatcheries are the last hedge against extinction. Everywhere else, however, science increasingly shows that hatchery fish survive at about one tenth the rate of their wild counterparts. In most cases, just as many total fish would have been produced if there were no hatchery at all.

On September 10, 2001, a federal judge in Eugene, Oregon, ruled that the National Marine Fisheries Service had made no genetic distinction between imperiled wild coho salmon on the Oregon Coast and abundant hatchery coho running through the same rivers. The implication of his decision was that either the wild fish needed to lose protection of the ESA or that hatchery fish should gain it. Although a higher court subsequently reinstated protection for the wild fish while it considers an appeal, the issue has many people in the region wondering what difference, if any, there is between wild and hatchery salmonids, the family that includes salmon and steelhead.

For several decades, there has been a growing awareness in both the scientific and the lay communities that the fish reared in a hatchery, and their subsequent offspring, are indeed different from their wild counterparts in terms of basic survival of individuals, specific runs, and the species as a whole.

This paper considers the principle survival strategy salmonids have perfected over millennia in Northwest waterways and shows how human tinkering through the use of hatcheries has greatly harmed that time-tested strategy of successful adaptation to complex and dynamic natural environments. Interactions between hatchery and wild salmonid populations have generally been harmful to wild salmonids and their continued survival by disrupting and eliminating successful and diverse adaptations. Those losses in turn have led to reductions in the genetic diversity of salmon populations and, more importantly, reductions in the diversity of life-history strategies within individual salmonid populations that are essential to preserving the evolutionary vitality of wild runs.

We will argue that in some extreme cases, hatcheries may be required to keep alive the last traces of a distinct genetic line. Keeping some representatives alive protects an irreplaceable line of behavior and genes, both of which may be critical to the recovery of a functioning wild population. Everywhere else, the best available science tells us, hatcheries can be expected to harm rather than help struggling wild runs and should therefore be eliminated. The ESA requires preserving not only wild species, but "the ecosystems on which they depend." Hatcheries are not functioning ecosystems and skirt the requirement to protect the land that nurtures the fish. If hatcheries will not save the few wild runs that remain - and the best science out there says they won't - then the only solution is to protect the habitat in which salmonids evolved over millennia and on which their future depends.

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