Sunday, October 10, 2010



By Bill Bakke
Native Fish Society

There is a continuing debate that has spanned 153 years of salmon management and that is whether salmon are locally adapted animals to their home streams through what Darwin (1859) called natural selection.  The debate continues today and will be present in the future, shaping salmon and steelhead management.  In Oregon, Washington, Idaho, and California salmon and steelhead are still released from their river of origin into other rivers in the name of enhancement for fisheries.  This lack of conservation management policy for and understanding of salmonid biology, genetics, and life history and respect for the fish is one issue the Native Fish Society is committed to changing.

I have researched the historical literature on this subject to provide a context for proper salmonid management.  It is a fundamental problem that should no longer be a factor of deliberate fish management.  Transferring fish from one watershed to another is not supported by history or by science, but it takes the many voices of informed people to make a administrative changes. 

Hatchery fish management practices that encourage straying of hatchery fish from one watershed to another is another form of this same problem and it has the same detrimental, degrading effect on wild, native stocks. 

Andrew Lang: “…each river has its own peculiar race of fish…We have now shown that salmon undoubtedly return to the river where they have spawned, and where they belong to the race of fish that inhabit that particular river.”  (N.P. Wilkins, Atlantic Salmon Trust)

George Perkins Marsh:  “Fish (salmon) are more affected than quadrupeds by slight and even imperceptible differences in their breeding places and feeding grounds.  Every river, every brook, every lake stamps a special character upon its salmon…which is at once recognized by those who deal in or consume them…”  (George Perkins Marsh, Man and Nature)

Alvin C. Anderson:  He was the inspector of fisheries in British Columbia, and he “…realized that the Pacific salmon are organized into separate local populations, with each river having its own distinct stock.  He recognized that the supply of salmon in a river depended upon the number of spawners in that river.  Anderson’s views reflected earlier recognition that Atlantic salmon faithfully returned to their home stream.  Acceptance of the stock concept led managers of British Columbia’s salmon fishery to limit fishing effort by restricting both the timing of fishing and type of gear permitted.” (David Montgomery, King of Fish, 2003, page 132)

R.D. Hume:  “He recognized that salmon stocks in different rivers were distinct and adapted to their home stream.  Consequently, he advocated using stocks from streams similar to those into which they were to be released as the key to successful salmon breeding.”  (David Montgomery, King of Fish, 2003, page 165)

David Starr Jordan:  “The first president of Stanford University and the leading academic salmon biologist of his day, shared (Livingston) Stone’s view, stating: ‘It is the prevailing impression that the Salmon have some special instinct which leads them to return to spawn on the same spawning grounds where they were originally hatched.  We fail to find any evidence of this in the case of the Pacific Coast salmon, and we do not believe it to be true.” (Jordan and Everman, 1902 in King of fish, 2003, page 159)

Willis Rich:  “It is obvious that the conservation of the species as a whole resolves into the conservation of every one of the component groups…Diverse evidence points so clearly to the existence of local, self-perpetuating populations in the Pacific salmon that…practical conservation measures be based upon the acceptance of the ‘home stream theory’ as an essentially correct statement.”  (David Montgomery, King of Fish, page 165)

Willis Rich:  “It is apparent then that one of the first requirements of a sound conservation program must be the determination of the extent to which the species to be conserved is broken up into local populations.  The defining of specific populations is concerned to a considerable extent with the determination of the geographical limits occupied by each.”  (Willis Rich 1939)

Willis Rich:  The importance of the fact that the salmon and steelhead return as adults to their home streams and tributaries is obvious; it is essential that each independent, self-perpetuating population of fish be preserved if depletion is to be avoided.” (Willis Rich 1948, Special Scientific Report No. 51. U.S. Fish and Wildlife Service)

W.F. Thompson:  “This principle applies to the salmon along our coasts.  Each stream or lake has its own extremely complex characteristics, and if salmon live in one of them we find that these salmon are adapted in an equally complex way to that environment.  We are far from understanding these two complexes, the fish and the environment, but we do know that in order to return to the place for which it has been fitted, the salmon returns from the sea to its home stream, there to meet and breed with its own kind.  Thus it develops and perpetuates the genetic characteristics which fit it for survival in the stream.  So we have a multitude of groups of salmon, each self-perpetuating which we loosely term races, and which the scientists calls gene pools, each fitted to survive in a particular home.  If it leaves this home the race either dies off or readapts.”  (W.F. Thompson. 1965. Science 150: 3705: 1785-1789)

Roderick Haig-Brown:  “The river of birth is the river of return.  Each species of salmon, each race within each species, by long selection, is ideally adapted to make best use of its own watershed, its own tributary and subtributary, even the gravel quality and water quality of its own particular spawning area.”

“What is now clear is that each species is made up of thousands of different ‘races,’ each specialized to its own freshwater environment by thousands of years of adaptation.”   (Roderick Haig-Brown, The Salmon, 1974, pages 9 and 30)

John Volpe:  “Wild salmon, however, return to their natal river to spawn and each generation is repeatedly tailored by natural selection to the conditions of the river.  Each river system ‘selects’ only those individuals possessing traits that are most suited to survive in the local environment.  Thus, each adult wild salmon returning to spawn is an organic extension of not only its parents, but also of the river that produced it.”  (John Volpe, 2002. Suzuki Foundation)
Science is clear about the biological effect of hatchery fish on native, wild populations.  Whether these hatchery fish are released into non-natal rivers or stray into them from releases into other rivers, the impacts are the same.  The stray hatchery fish interbreed with wild salmonids and degrade their reproductive fitness and success. 

Since hatchery fish are able to spawn successfully, they compete at the juvenile stage for food and rearing space.  The abundance of hatchery fish is also attractive to predators and can increase mortality on wild salmonids.  In addition, fishing mortality is increased on wild fish that are mixed in with hatchery fish.  All these factors limit the productivity of wild salmonids and create multiple obstacles to their health and recovery.

The Oregon Department of Fish and Wildlife does not have an administrative rule to regulate the transfer of fish among watersheds.  In 2003 the department adopted the Hatchery Fish Management Policy where it states that hatchery fish are to be managed by objective and Objective 2 states: “Contribute toward the sustainability of naturally produced native fish populations through the responsible use of hatcheries and hatchery-produced fish.”

However, there are on-going transfers of salmon and steelhead among Oregon watersheds.  Information contained in the 2010 Hatchery Operations Plans shows that there are 27 stock transfers of fish into watersheds where they are not native. 

The ODFW apparently does not subscribe to the factual basis that salmonids are locally adapted and to their own research and that of others showing that the best conservation principle is to protect locally adapted fish populations.

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