Endangered Salmon and the Effects of Mixing Wild and Propagated Fish

By Dr. John Nickum

Question:  Is it true that the National Marine Fisheries Service (NMFS), following a decision by Judge Michael Hogan, has proposed to count hatchery produced salmon as equivalent to wild salmon and to give them the same value with respect to endangered species recovery?  Can you explain the “logic” of such a decision?

The Old Professor responds: 

Yes, indeed, your statement is the essence of Judge Hogan’s decision.  He ruled in 2001 that the NMFS must include both naturally spawned salmon and hatchery spawned salmon when they assess the condition of salmon populations for purposes of the Endangered Species Act (ESA).  At the time of his decision, 27 populations of salmon and steelhead were listed as threatened or endangered under definitions of the ESA.  Subsequently, the NMFS issued proposed plans and policies to comply with Judge Hogan’s decision and requested public comment on the proposals.  Not surprisingly, controversy has ensued.  What appears to be “logical” to some interested parties appears to be totally illogical to others.  Can I explain the “logic” involved?  No, but I will offer some comments and observations.

The ESA, interpretations of it, and subsequent actions and decisions to implement the Act have led to very complicated situations.  If the ESA is interpreted to require certain numbers of the entire species, very few, if any trout and salmon can be considered to be threatened, let alone endangered.  However, if sustained natural reproduction and survival of specific spawning populations is required many trout and salmon populations are in serious trouble.  Judge Hogan’s decision seems to focus on the harvestable numbers of the populations in question.  The harvest does not distinguish among fish from wild spawning versus fish from hatchery spawning.  There is no evidence that one is more susceptible to harvest than the other, so all individuals should count toward the total population.

However, if the goal is a sustainable population based on natural spawning, only wild spawned fish should be counted.  Nearly everyone prefers to rely on natural spawning, if it is adequate to maintain the population.  Why spend the time and money for a hatchery program, if nature can supply everything needed?  Why take the chance that budget cuts, or a bureaucratic decision, will eliminate the hatchery program and with that decision the fish dependent on the hatchery?  The problem rests in the fact that, for many salmonid populations, natural spawning is extremely difficult and frequently impossible.  The spawning habitat has been destroyed, or access to it is blocked by dams, culverts, or pollution.  The hatchery becomes the only way to “bridge over” the broken phase of the life cycle.

Environmental literature concerning salmon and, to some extent trout, often discusses the “4-H’s”; habitat, harvest, hydro, and hatcheries; as the primary causes of the salmonid population problems that have brought some populations to the brink of extinction.  Judge Hogan’s decision does not address all these factors, but leaves the action plans to the NMFS. 

A major problem lies in the fact that the effects of the “4-H’s” are fundamentally and dramatically different.  The effects of actions, such as habitat degradation or destruction;  unsustainable harvests; or hydrologic changes ranging from altered flows, to impassable dams, to total dewatering; act to reduce fish populations to unsustainable levels.  The effects of hatcheries are quite different.  The hatchery produced fish tend to mask the effects of the other actions, rather than to contribute directly to the reduced numbers.  The hatchery production can lead to a false sense of security and decisions to do nothing about the other three “H’s”, the major contributors to the problem.

I acknowledge that some individuals contend that “hatchery fish” are innately inferior to wild fish.  Although hatchery production practices, inadequate budgets, and unenlightened administrators have caused some hatcheries to produce “inferior” fish, there is no fundamental reason hatchery spawned fish must be inferior.  I suggest that statements claiming them to be inferior are based primarily on prejudice, not science.  It is essential to discriminate between basic biological characteristics and behavior or appearances caused by hatchery production methods. 

In some cases, salmon populations seem to have locally adapted characteristics.  Fish managers must recognize that it often is not possible to replace local wild populations with hatchery produced fish produced in other locations.  For example, experience has shown that fish from coastal populations in western Washington cannot be used to re-establish populations in Puget Sound; apparently due to different local adaptations.

So, what should be done?  If the goal is simply to have fish for harvest, it makes sense to consider all fish, wild spawned or hatchery spawned as part of the total population.  If the goal is to have sustainable, naturally spawned populations that do not require continual human intervention, then the fish must have natural habitat in which to spawn and live, and they must be protected from over-harvest, de-watered streams, and toxic levels of pollution.  I think that the goal of the ESA is the latter.  Judge Hogan apparently believes it is the former.  Which is the goal of our overall society remains to be determined.          

Send your questions on biology and fish management to the “old professor” at:  Trout Talk, Colorado Trout Unlimited, 1320 Pearl Street, Suite 320, Boulder, CO 80302.

About The Author

Dr. John Nickum is a retired fisheries biologist whose 40+ year career included teaching and research at Cornell University, South Dakota State, and Iowa State, and most recently, working as the Regional Science Officer for the U.S. Fish and Wildlife Service in Denver.  He currently resides in southwest Utah.