The Role of Hatcheries in Pacific Salmon Management White Paper

Oregonians In Action P.O. Box 230637 Tigard OR 97281 (503) 620-0258 http://www.oia.org Email:  oiaec@teleport.com Wild Pacific salmon and steelhead populations in the Pacific Northwest have been in a state of general decline since the late19th century, primarily due to the burgeoning human population growth in this region with attendant loss of natural spawning and rearing habitat from logging, construction of hydroelectric dams, and agricultural and forestry practices. In more recent years, factors such as declining biological productivity in the North Pacific Ocean, over-exploitation in mixed stock fisheries and the high seas gill net fishery, and greatly increased populations of predators, especially seals and sea lions, have also played a role. It has long been recognized that due to the above factors, declining wild spawning and rearing habitat would support only a minimal recreational and commercial fishery on naturally reproducing stocks. Although hatcheries are not a cure-all by any means, they have historically provided a very popular, and internationally used method of mitigating this problem and today many Pacific Salmon runs consist mostly of hatchery fish. Thus, for nearly a century, hatcheries have successfully accomplished the twin goals of (1) helping to compensate for declining naturally spawning populations, and (2) supporting a sustainable recreational and commercial fishery. Recently, however, hatcheries have come under attack by some who would apparently prefer to have small, but completely wild, salmon/steelhead populations that would perpetuate themselves solely by natural reproduction. This would be accomplished by eliminating hatcheries, and restoring Pacific Northwest rivers and lakes to 19th century conditions by breaching hydroelectric dams, and by greatly reducing forestry and agriculture. These draconian measures would have significant negative social and economic impacts. To promote this agenda, hatchery opponents typically raise theoretical issues about the genetic fitness of hatchery vs. "wild" fish based on assertions that hatchery reared salmon are genetically adapted to sheltered conditions during their few months of hatchery rearing before they migrate to the ocean. They are thus said to be inferior to wild fish that have adapted to the harsher conditions in rivers and streams where they hatch and rear before migrating to the ocean. The fact that both hatchery and wild fish are acted upon by the same evolutionary forces during the majority of their life cycle while they live in the ocean is usually conveniently ignored. Another widespread perception is that salmon propagated in hatcheries, either for the purpose of restoring sustainable fish populations or boosting fish production for harvest, will adversely affect the genetic diversity and fitness of wild fish populations. However, this assumption is clouded by uncertainty leaving it open to interpretations based on opinion and philosophical perspective (Williamson, 2001). Nevertheless, it has become dogma accepted as true by many fisheries biologists and managers. Campton (1995) has provided a thoughtful overview of this perception and concludes that there have been too few well-designed studies to provide the hard data needed to test its assumptions. Thus, fish hatched and reared in hatcheries are alleged to have tainted the gene pool of wild stocks when they intermingle and spawn naturally with them upon their return from the ocean - as many of them do. Also, most of the attack on hatchery salmon is based on comparisons between divergent stocks of fish, which is not a true comparison between wild and hatchery fish from the same stock. Another major element of contention about the use of salmon hatcheries is the question of whether hatchery reared salmon differ too much genetically from naturally spawning, "wild" salmon. Disagreement on this subject is partly semantic, because the term "genetic difference" is used in different contexts when referring to the individual and population levels of biological organization. Surprisingly, the Endangered Species Act (ESA) allows the term "species" to be legally used to describe "full species," "subspecies" or "distinct population segments" of full species. Because salmon/steelhead populations that spawn in one part of a watershed may not commonly interbreed with those that spawn in other parts of the same watershed, the 6 separate species of salmon (chinook, coho, sockeye, etc.) are divisible into hundreds of individual stocks of fish; each with certain morphological and physiological differences. Regardless of the legal definition of species allowed by the ESA, the gene remains the fundamental unit of heredity. All members of a species are endowed with the same set of genes. A gene pool is the totality of genetic material possessed by a species and contains the instructions for all the inherited traits that are the genetic resources of the species. When these genetic resources are lost from a species gene pool, they cannot be restored. Many wild salmon/steelhead populations are now so small that they retain very little genetic diversity. It is now entirely possible that there is greater genetic diversity in hatchery salmon populations than in some wild populations. The term "allele" refers to different forms of a gene. For example, the blood types A, B and 0 are alleles of a single gene. At the individual fish level, two fish are genetically different if one individual possess an allele or alleles that the other does not. Therefore, the statement "hatchery fish are genetically different from wild fish" is true if and only if there is an allele or alleles that occurs only in hatchery-bred fish, and a complimentary allele or alleles that occur only in "wild", naturally spawned fish. Such unique alleles would be tremendously important. However, no such alleles are known to exist, and probably do not exist in nature. All hatchery-reared salmon/steelhead are ultimately descended from naturally spawning "wild" fish, and possess all the genes found in "wild" fish. There is no known genetic mechanism that would result in the creation of an allele found only in artificially propagated hatchery fish. Further, there is no known mechanism that would preclude the hatchery allele, if one existed, from being introduced into naturally spawning populations when fish of hatchery origin spawn naturally as many of them do. Thus, at the individual fish level, there is no genetic difference between hatchery-bred and naturally-spawned salmon. At the population level, there may be differences in the frequencies of inherited traits between populations. Similar differences in the frequencies of inherited traits can also be observed between naturally spawning populations and between different hatchery populations as well as between hatchery and wild populations. These differences in frequencies are referred to as genetic differences because they describe variation in the organization of genetic material among populations. An example of this type of variation in human populations would be different frequencies of blue-eyed people in different geographic locations. Unfortunately, some workers have erroneously interpreted gene frequency differences to be adaptive, when there is no evidence that this is the case. A plausible and probable alternate explanation is that gene frequency differences result from small founding populations and limited gene flow. In this case, no (adaptive) selection is necessary. Again, hatchery fish are not genetically different, as a class, from "wild'' fish even though the endangered species act allows them to be labeled as such. The purpose of the present document is not to say that naturally spawning salmon are not needed. Healthy, naturally spawning salmon populations are a national treasure. We are also not prepared to state that all salmon conservation problems can be solved with hatchery-reared salmon. There have been poor hatchery practices in the past and some hatcheries were not originally sited on a sound biological basis. What is needed is a biologically sound blend of both hatchery and wild fish based on known scientific facts. This will assist the public, which has the ultimate say in the matter, in deciding on the difficult trade-off required for the conservation and management of viable Pacific Salmon and Steelhead populations for future generations. In summary, salmon and steelhead hatcheries have historically had the twin goals of (1) helping to recover and conserve natural spawning populations, and (2) supporting sustainable commercial, recreational, subsistence, and ceremonial fisheries. Most hatcheries in the Pacific Northwest and Alaska have been operating for many decades and have generally been very successful in producing fish for harvest and compensating for declines in wild salmon populations. Hatcheries are critical to maintaining future recreational and commercial fishing in the Pacific Ocean and in meeting Treaty harvest obligations. Like it or not, hatchery populations now comprise a major component of Pacific salmon/steelhead species gene pools. This year (2001) for example, 60-80% of salmon that will be harvested originated in state, federal, and Tribal hatcheries. Given the additional 20-40 million in human population growth predicted for the Pacific Northwest in coming decades, it is almost certain that the downward trend in purely wild salmon populations will continue. For example, the east coast of the US, Europe, China, Japan, and Korea formerly supported large populations of purely wild salmon. They no longer do so and it is unlikely they will ever do so again (Lackey, 2001). Not only did today's hatchery salmon originate from the eggs and sperm of naturally reproducing salmon populations, hatchery produced fish have been thriving and returning to Pacific Northwest Rivers in unprecedented numbers. Unfortunately, these same hatchery fish are now being labeled genetically inferior, hunted down and clubbed, and their eggs sold as fish bait. There is a very real danger that present anti-hatchery policies will, if pursued, reduce salmon/steelhead populations to the point that there will be no significant recreational or commercial fishing for decades to come. In addition, the deliberate destruction of these hatchery populations by natural resource management agencies may actually be destroying genetic material needed for the continued health of salmon populations in general. Once genetic material is lost from a species gene pool, it can never be recovered. The populations of some remaining "wild" fish are now so small that their genetic diversity has been reduced to the point that they may be unable to grow sufficiently without an infusion of genetic material from hatchery fish. Although genetic management of naturally spawning fish populations is not possible, inherited traits in hatchery salmon populations can be readily adjusted to suit management goals and objectives. Establishing and maintaining hatchery populations with a prescribed pattern of life history variation similar or identical to the naturally spawning populations with which they may interbreed is an attainable management goal that could ameliorate concerns about detrimental interactions. At the present time, hatchery runs are thriving and must not be destroyed. Hatchery fish that are now being wasted are a resource that should be used proactively in recovery efforts. As one example, surplus adult salmon could be outplanted in barren habitats. This would be unsuccessful in some cases but would yield positive results in others. Any success would be highly cost effective because the fish that already exist are going to waste. Meanwhile, "had good salmon fishing lately -- Thank Hatcheries." October 2001 Donald F. Amend, Ph.D. (Fisheries Biologist, Ret.) Jim Lannan, Ph.D. (Fisheries Biologist, Ret.) William J. McNeil, Ph.D. (Fisheries Biologist, Ret)

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