Affidavit to federal district court regarding hatchery supplementation risks to native salmonids in the Imnaha River, Oregon. UNITED STATES OF AMERICA, et al., Plaintiffs, V. STATE OF OREGON, et al., Defendants. Case No. 68-513 MA
The following affidavit is that of Mark Chilcote, the Fish Conservation Program Leader for the Oregon Department of Fish and Wildlife. He addresses the risks associated with using hatchery fish to rebuild wild steelhead populations, a technology called supplementation that the Tribes favor to increase fish production in the Columbia Basin. He also evaluates the Tribes monitoring and evaluation plan for hatchery supplementation, pointing out the problems. It is because of this review, that the Tribes decided to not seek an injunction against ODFW in federal court to force the state to go along with their hatchery program. Not wanting to fail in court, the Tribes have redirected their effort to the Oregon Legislature where they are attempting to exempt all streams above Bonneville Dam on the Columbia River in Oregon from the Oregon Wild Fish Managment Policy. By exempting these streams from the Wild Fish Management Policy, the Tribes are evidently hoping to curb the states conservation authority over steelhead and salmon that are listed as federal protected species under the ESA. If the states conservation mission can be blocked, the tribes apparently are hoping they can use hatchery supplementation without regard for the conservation of wild populations or have the burden of adequate evaluation of their hatchery programs.
I, Mark Chilcote, being first duly sworn to oath, depose and say:
I make this affidavit of my own personal knowledge and am competent to testify to the facts contained herein. I am the Fish Conservation Program Leader within the Natural Production Program of the Oregon Department of Fish and Wildlife (ODFW). I received a B.S. degree in Fisheries Science from Oregon State University in 1972. In 1976 I received a M.S. degree in Fisheries Science and Genetics from Oregon State University. In total, I have 23 years of experience working as a fish biologist in the States of Alaska, Washington, and Oregon. My area of specialization has been conservation of wild fish populations and interactions with hatchery fish. I have conducted original research on interactions and differences between wild and hatchery steelhead and have published 8 different articles in peer-reviewed scientific journals. In my current role as Fish Conservation Program Leader I have conducted two comprehensive species status review and regularly provide advice to ODFW on fish conservation issues and policy. I was an expert witness in the Imnaha steelhead dispute last year and am familiar with the biological issues associated with managing steelhead in the Imnaha River.
The purpose of my affidavit is: (a) to provide the rationale for why ODFW believes supplementation is a methodology that has yet to be proven successful; (b) to describe why supplementation is considered a potential risk to the reproductive health of wild populations; and (c) to describe the key elements of scientifically acceptable supplementation program.
INTRODUCTION
While the concept of adding more spawners to a depressed wild population seems like a logical way to rebuild natural, self-sustaining populations, in practice, the results have not proven successful. Not only has this practice failed to rebuild natural populations, but also each year more evidence comes to light that suggests supplementation can do harm to the productive capacity of wild populations. Therefore, any program to rebuild wild populations by adding hatchery fish to the spawning population must be subject to rigorous monitoring and evaluation, to limit damage if identified, and maximize benefits, if any.
SUPPLEMENTATION - AN UNPROVEN METHODOLOGY
Although hatchery programs have been successful in producing adult salmon and steelhead for fisheries, which do not have to survive and reproduce in the natural environment, the successful use of hatchery fish to rebuild depressed wild populations is notably unreported in the scientific literature.
During the 1960s and 1970s, juvenile hatchery reared coho salmon were released into many streams on the Oregon coast. McGie (1980) investigated the success of these releases and concluded that they ...had no measurable influence on adult escapement.
This conclusion was supported by the findings of a more detailed study conducted by Nickelson et al (1986). They found that supplementing depressed populations of coho salmon on the coast of Oregon with pre-smolts from a domesticated hatchery coho stock resulted in no increase in the number of stream reared adult coho returning to spawn in subsequent years. More recently, Solazzi et al. (1998) reported the results of a study conducted with a hatchery broodstock selected because it spawned at the same time as the local wild population. They found no difference between supplemented and unsupplemented streams in terms of juvenile coho abundance or numbers of returning adults.
The failure of supplementation programs to rebuild wild populations is not restricted to these studies on the Oregon coast. Miller et al. (1990) in a review of 26 supplementation projects on a wide variety of salmonid populations in the northwest, found no quantifiable evidence of any benefit to wild populations. Similar results were obtained by the Independent Scientific Group (ISG) in their review of Columbia Basin fish and wildlife programs (ISG, 1996). They conclude:
Reviews of supplementation (Miller et al. 1990; Steward and Bjornn, 1990, Hilborn and Winton, 1993; Winton and Hilborn, 1994; Bowles, 1995) indicate that in those few instances where supplementation projects were conducted in a rigorous enough manner to permit evaluation, supplementation was rarely successful in increasing natural production, and often significant risks were incurred (Reisenbichler and McIntyre, 1977; Nickelson et al., 1986; Reisenbichler and McIntyre, 1986; Waples and Do, 1995; Allendorf and Waples, 1996).
Turning specifically to the Imnaha steelhead, supplementation does not appear to have had a positive influence on the abundance of returning wild fish. This is clear from an examination of the counts of wild fish returning to Little Sheep Creek before and after supplementation. In the period following the implementation of supplementation, the annual number of wild adults returning to Little Sheep Creek ranged between 17 and 128 fish. In the five years before potential supplementation effects the return of wild fish ranged between 56 and 163.
The counts of wild fish returning to Little Sheep Creek before and after supplementation were consistent with the patterns of wild returns elsewhere. For example, since 1993 the pattern of wild fish abundance in Little Sheep Creek appears similar to the pattern of spawner density estimates for Camp Creek (within the Imnaha basin and Joseph Creek (within the Grand Ronde basin). Camp Creek probably receives some hatchery strays from the Imnaha, while no hatchery steelhead have ever been observed in Joseph Creek. Therefore, the abundance of steelhead in these three locations appear to be controlled primarily by factors which they have in common, such as downstream passage and ocean conditions. Whether or not they are supplemented with hatchery fish does not seem to have had any impact, at least not since 1993.
In light of the record on supplementation, both generally and specific to steelhead in the Imnaha, it is unwarranted to assume that adding hatchery fish to the spawning population will have a positive effect on the abundance of wild steelhead. The Nez Perce have been unable to provide any evidence of a successful program.
SUPPLEMENTATION - A RISKY METHODOLOGY
While there is no evidence of supplementation being a success, there is evidence that supplementation poses a risk. There is a growing body of scientific evidence that hatchery steelhead do not reproduce as successfully as wild fish (Reisenbichler 1997, Reisenbichler and McIntyre 1977, Leider et al. 1990) Other studies also demonstrate that genetic differences that impact survival exist between hatchery and wild steelhead (Berejikiian 1995). Similar findings have been reported for other anadromous salmonids by Fleming et al 1996, Fleming and Gross 1994, Swain and Riddell 1990 and Waples 1999.
Although testable differences between hatchery and wild fish exist, the specific mechanisms that cause such differences are not yet clearly understood. However, it is certain that some of the mechanisms are genetic. When the source of a hatchery broodstock is not from the local wild population, the resulting hatchery fish are likely to be different from the wild population. This differences will reduce the reproductive potential of the hatchery fish. It also will cause a decrease in the reproductive performance of any wild fish which interbreeds with a hatchery fish.
Although it may be possible to alleviate this problem through the use of local wild fish for hatchery broodstock, domestication of such fish within a hatchery environment is unavoidable. Domestication causes genetic changes. For example, in the wild less than 3% of the juvenile fish that hatch from the eggs survive to emigrate to the ocean as smolts. In contrast, at least 85% of the juveniles that start out life in a hatchery environment survive to become smolts. This low egg to smolt survival is the wild is natures way of eliminating less fit individuals from the population and keeping the species as a whole genetically healthy. Placing steelhead juveniles in an unnatural environment, such as a hatchery, where this process can not occur results in the concentration of maladaptive traits within the hatchery broodstock. These deficiencies are largely undetectable using currently available tools for genetic analysis, or by physical observation. However, when fish from such a hatchery stock are returned to the wild and attempt to reproduce, the accumulated genetic change is manifested in reduced survival of their offspring. In addition, the reproductive success of wild fish can be seriously reduced if they interbreed with such hatchery fish. Thus far, methodologies to control this domestication process in hatchery broodstocks have not been adequately developed or evaluated.
If the difference in reproductive capacity between hatchery and wild fish is genetically based and is as large as some of these studies suggest then the interbreeding of hatchery fish with wild fish could result in a serious reduction in the health of the wild population.
In addition to differences caused by genetic change, the hatchery environment itself can modify physical characteristics of hatchery-reared fish in a non-genetic manner. For example, it is possible that hatchery fish select inferior locations to spawn because they have not imprinted on the areas within a stream best suited for hatching and rearing juveniles. Another possibility is that hatchery fish, because of their extremely crowded rearing environment, are exposed to more diseases than they would be in the wild. Therefore, the chance that they are carrying a disease they can spread to other naturally spawning fish or their offspring is higher than it is for wild fish. As with the genetic-based changes, hatchery methodologies to lessen environmental based change in hatchery fish need further development and evaluation. This fact makes it imperative that any program to purposely use hatchery fish to help rebuild a wild population must contain a comprehensive monitoring and evaluation program.
Regardless of the mechanism, it is clear that the greater the presence of hatchery fish in the natural spawning population, the greater the risk to natural production of fish in a stream. For example, Chilcote (1998) found that among 26 steelhead populations throughout Oregon, the rate of production was lowest for streams with the highest percentage of hatchery fish in the natural spawning population. The more hatchery fish, the less productive the population.
In conclusion, supplementation is a risky methodology that must be used with considerable caution. This is not just the opinion of ODFW. The aforementioned studies and several recent scientific review concerning the use of hatchery fish (Independent Scientific Group, 1996; National Research Council Upstream, 1996; National Fish Hatchery Review Panel report, 1994) all come to the same conclusion. (additional scientific publications to be added to this list are the Independent Scientific Advisory Boards Return to the River, 1996; Independent Scientific Advisory Boards report Review of artificial production of anadromous and resident fish in the Columbia River basin, 1999, and the Independent Multidisciplinary Scientific Teams report: Review of the hatchery measures in the Oregon Plan for Salmon and Watersheds, 1998.)
ELEMENTS OF A SCIENTIFICALLY ACCEPTABLE SUPPLEMENTATION MONITORING AND EVALUATION PROGRAM AND CRITIQUE OF THE PROPOSAL OF THE NEZ PERCE TRIBE.
Supplementation is an unproven and risky method for rebuilding wild populations. However, it is a methodology that conceptually holds promise and may eventually be developed into a useful strategy. Thus, in spite of the known risks and minimal likelihood of success, experimental supplementation projects are warranted if knowledge is gained on the future potential of this methodology as a recovery tool.
However, such supplementation projects should be designed to address certain concerns before they are undertaken. For example, does the program have clearly stated objectives and realistic criteria for success or failure?; and is there a carefully planned and executed monitoring and evaluation plan to determine whether the supplementation program worked or not?
As stressed by ISG (1996), rigorous monitoring and evaluation is critical to any supplementation program. This is because it is know that the supplementation technology is not fully developed, the risks are high, and to date the benefits of supplementation have not been demonstrated. For the reasons described in the following paragraphs, ODFW does not believe the evaluation approach described by the Nez Perce Tribe in a letter dated March 5, 1999 to Burnie Bohn and Bruce Eddy is adequate.
(a) First, the monitoring and evaluation plan proposed by the NPT is deficient because it does not state the objective of the evaluation. The objective of the evaluation should be to determine if outplanting adult hatchery steelhead is an effective tool to increase self-sustaining abundance of a wild steelhead in the Imnaha basin. All study components and associated activities should contribute to the achievement of this objective.
(b) Second, the evaluation plan is deficient because it contains no definition of success. As proposed, the NPT plan would generate several unrelated data sets without any structure for interpretation. Success should be defined as specific terms such as the density of wild steelhead spawners will be statistically greater after two generations in the streams that were supplemented with hatchery fish compared to streams that were not supplemented. From such a definition of success an experimental design would logically follow. as the evaluation plan developed by the NPT currently exists, the experimental design has no logical flow.
(c) Third, the evaluation plan is deficient because it relies largely on information being generated from ongoing (and somewhat unrelated) research projects and activities. For example, the determination of smolt run timing or the determination of travel time of PIT tagged steelhead and spring chinook both seem somewhat irrelevant to a evaluation of steelhead supplementation. However, the NPT appears to claim these activities as a component of their supplementation evaluation program. Other activities proposed in their evaluation plan could have more relevance such as monitor the density and selected life history characteristics of juvenile steelhead in streams of the Imnaha River. However, such information would only be useful if it is clearly placed in the context of a specifically defined, stand alone supplementation evaluation proposal. the NPT make no such proposal. Currently, all indications suggest the NPT is unwilling or unable to secure the proper technical and financial resources to develop and implement an evaluation of the proposed supplementation activity.
(d) Fourth, the evaluation plan is deficient because information collection activities are proposed without an explanation of purpose or underlying question being asked.
(e) Fifth, the evaluation plan is deficient because it would fail any independent scientific review due to the plan being incomplete, vague, and without logical integration.
CONCLUSION
Using hatchery fish to help rebuild depressed wild populations is an unproven and risk methodology. In the case of the Imnaha steelhead population there is some evidence from the experience of supplementing Little Sheep Creek that adding large numbers of hatchery fish to naturally spawning populations resulted in no natural production benefit. In addition, there is no evidence that this population is at serious risk of demographic extinction. Indeed, the ISG (1996) states that unrealistic supplementation programs may actually ...pose significant genetic and demographic risks to the target stock. In light of these facts, any steelhead supplementation that takes place in the Imnaha should be confined to a very restricted area and carefully evaluated. Without a careful evaluation there is no justification for even an experimental program of supplementation.
DATED this 9th day of April, 1999
Mark Chilcote