HATCHERY SUPPLEMENTATION EVALUATED AGAIN





	In the January 1998 issue of "Fisheries" a publication of the American


Fisheries Society, author Robert M. Bugert evaluates hatchery


supplementation case histories on Washington State's Chiwawa, Methow, and


Tucannon rivers.


	This review is another effort to establish the scientific efficacy of using


hatcheries to rebuild wild salmonid runs in the Columbia River and other


rivers in the region.  The Power Planning Council has spent tens of millions


of dollars on this technology and the Bonneville Power Administration has


funded the development of a scientifically based supplementation process


call the Regional  Assessment of Supplementation Projects (RASP) and a


scientific evaluation of over 300 supplementation projects on salmon.


Scientific evaluation of supplementation, so far, only shows that it does


not work and it has dredged up some knotty problems.  Yet the fish agencies


and tribes continue their effort to find a new way to justify their hatchery


programs and continue the flow of millions of dollars of federal money to


support hatcheries state and tribal agencies advance.


	According to Bugert, many of the supplementation efforts are failing, but


the reasons for their failure is not fully known.  He holds out for this


technology, saying, "Hatcheries could....help diversify salmonid life


histories."


	Bugert refers to the definition of supplementation developed by RASP as


the basis for guiding all supplementation programs in the basin:  The RASP


defines supplementation as: Supplementation is the use of artificial


propagation in an attempt to maintain or increase natural production while


maintaining the long-term fitness of the target population and keeping the


ecological and genetic impacts on nontarget populations within specified


biological limits.


	To Bugert this means that hatchery supplementation is used to increase


production, but do it in a way that leaves no footprints; release smolts


that are innocuous to their natural counterparts; the trap used to capture


adult spawners must be transparent during the passage of other species, and


supplementation will not sidestep the underlying causes of declining


salmonid abundance.


	According to a study by Miller and the National Research Council, most


accessible populations are now being supplemented and most are failing to


meet their objectives.  Bugert, in his article, seeks out the answers for


why supplementation is failing, saying "as currently used, supplementation


has low feasibility and high risk for many populations."  


	Is the theoretical promise of hatchery supplementation and advocacy for it


by the fish agencies, Power Planning Council, and tribes likely to result in


saving wild salmon and steelhead populations from extinction and result in


rebuilding them to a healthy condition?


	Hatcheries, including supplementation hatcheries, cannot circumvent the


causes of declining populations, but they can be versatile instruments used


to increase natural productivity if we recognize what they are good at, that


is, increasing early-life history survival, and apply this advantage within


the context of watershed management, says Bugert.  That is the promise of


supplementation: the increase of juvenile salmonids using techniques that


will not interfere with long-term fitness of affected and non-target natural


populations and the genetic diversity that is important for adaptation of


these populations to variable habitats, climate and oceanic conditions.


This natural diversity in native salmonid populations allows them to respond


successfully to fluctuating habitat conditions.  But he says, "Not only do


supplementation programs disregard the realities of variable environmental


conditions, but they also relentlessly battle ever-changing stream flows,


debris loads, and other vagaries of nature."


	Research has shown that while production can be increased through


supplementation, the productivity of the population being supplemented may


not increase.  In other words, hatcheries can increase adult production by


increasing smolt production, but the fitness of the affected population can


decline as the population experiences a reduction in traits that respond to


natural selection pressures.  The hatchery fish become more fit under


hatchery conditions and less fit for survival under natural selection


pressures.  Bugert says, "...the foundation of the supplementation concept -


that which encourages local adaptation - is arguably the most difficult


objective to meet."  This is because it is difficult to collect brood stock


on small streams where the target population spawns, to ensure that discrete


populations are collected, reducing the risk of outbreeding depression.


Outbreeding depression is where more than one population is collected for


broodstock, thus homogenizing the populations for artificial propagation and


removing local adaptiveness of distinct populations through mixing.  This


results in a homogenous hatchery population that may be genetically diverse,


but poorly adapted to the streams where they are expected to naturally


reproduce, affecting their survival fitness.  Research in Washington has


shown that hatchery fish have very low fitness and are likely to produce


very few if any adult progeny.  This is the opposite result expected from


hatchery intervention.


	What are the problems found in Bugert's case studies?  On the Chiwawa


River the adult trap for collecting brood stock, like many others in the


Columbia


Basin, is able to collect fish only in low flows, causing concern that traps


select for late-returning salmon. Less than 5 percent of the run was trapped


in 1990 and 1991.  In 1992, no fish were trapped  until May when the trap


was destroyed by high flows.  In 1993 the trap collected one third of the


run. "Analysis," says Bugert, "of marked carcasses recovered on the spawning


grounds of nearby streams showed that the trap prevented upstream migration


into the Chiwawa River and forces some Chiwawa fish to spawn among other


populations.  Increased vulnerability to outbreeding depression could have


resulted from this action."


	On the Tucannon River hatchery supplementation started in 1985.  The adult


brood stock trap missed one quarter of the run.  It could collect fish well


enough during low flows, but did not work during peak spring flows.  By


fixing the trap to collect fish more reliably in high flows caused a shift


in spawning distribution of  native steelhead and spring chinook to areas


below the trap. This dislocation increase from 18 percent of the run in 1986


to 56 percent of the run in 1992. This dislocation meant that fish were


spawning in areas less suited for survival than before the supplementation


project was started.  Since the trap intercepted late running salmon, during


lower flow periods, the supplementation project selected for late running fish.


	In the  Methow River,  three distinct populations of spring chinook have


been identified.  The Methow Hatchery was designed to collect and propagate


these discrete runs separately, in the attempt to maintain genetic diversity


of locally adapted salmon populations in three rivers, the Methow, Chewuch


and Twisp.   Again, the adult trap was not successful in collecting fish


during high flows with only 10 to 24 percent of the run being trapped.  In


order to improve the efficiency of the hatchery program it was decided to


trap spring chinook at Wells Dam on the Columbia below the mouth of the


Methow River.  The problem with this solution is that the three distinct


populations of spring chinook could not be separated at Wells Dam.


Depressed returns of spring chinook to the Methow River caused the fish


managers to assume the risk of with-in population diversity was a lower


priority than the assumed risk of extinction of the runs.


	Bugert identifies other issues relating to hatchery supplementation that


must be addressed.  One of these is the straying of hatchery fish so that


they do not  interbreed with native, wild salmonids and reduce the survival


fitness of the native population.  He says, "the incidence of stray fish in


hatcheries will probably increase if artificial propagation increases."


Stay hatchery fish are a problem for hatcheries attempting to implement


scientifically sound supplementation programs as well as attempts to


maintain locally adapted natural populations in rivers.  While elaborate


processes have been developed to detect and remove stray fish have been


developed it is plagued by the inability of traps to prevent stray hatchery


fish from spawning with wild salmon, not all hatchery fish are externally


marked so they can be identified, and methods for detecting stray fish is


stressful to unmarked or wild salmon.  Also, the fish agencies that operated


hatcheries have not developed a procedure to manage gene flow from hatchery


fish into other hatcheries and into wild populations.  This problem is so


serious that the Oregon Department of Fish and Wildlife have concluded that


stray hatchery steelhead in Oregon's Deschutes River are the cause of the


collapse of the wild steelhead run in that river.


	The creation of juvenile salmon acclimation sites for release into streams


is another problem.  Because of access problems in many watersheds related


to remoteness or snow pack in the spring months, acclimation sites for


supplementation projects are below the important salmon spawning areas.


This results in a change in salmon spawning distribution and survival.


Bugert makes the claim that when it comes to large, capital intensive


acclimation  sties flexibility and options for their use is less and the


ability to respond to needed changes is less.  


	Bugert concludes that hatchery supplementation and watershed improvement


must go hand in hand in order to successfully rebuild wild salmon runs.  But


this is seldom the case and salmon rebuilding efforts are counterproductive.


He argues that the premise RASP is built upon requires that hatchery


supplementation must be done within the context of a healthy productive


salmon habitat for it to work.  The hatchery supplementation program must


respect locally adapted populations and the habitat those populations are


adapted to for it to work.  This goes to the larger problem plaguing state


and federal policies that have traditionally separated salmon conservation


from habitat protection, relying upon hatcheries to overcome habitat


degradation.  "At this time, Bugert says, "hatcheries face overt


disincentives to operate in ways that support natural productivity."