BPA Fish and Wildlife FY 1997 Proposal

Section 1. Administrative
Section 2. Narrative
Section 3. Budget

see CBFWA and BPA funding recommendations

Section 1. Administrative

Title of project
Perf/Stock Prod Impacts of Hatchery Suppl

BPA project number   9005200

Business name of agency, institution or organization requesting funding
National Biological Service

Sponsor type   WA-Federal Agency

Proposal contact person or principal investigator

BPA technical contact   Tom Vogel, EWN 503/230-5201

Biological opinion ID   None

NWPPC Program number   7.3B.2

Short description
Evaluate costs and benefits for alternative sources of hatchery broodstocks in supplementation programs, test for domestication selection, and determines whether various modifications of the hatchery program can improve fitness of hatchery fish for reproducing and rearing and natural streams. Resulting genetic data on growth and survival will help project and understand the long-term consequences of supplementing wild populations of salmon and steelhead, and will facilitate planning to achieve maximum efficiency and conservation. These data will allow more complete consideration and analysis of questions such as whether or not to supplement rather than simply augument harvest?, what is the optimal capacity for a hatchery?, what is the optimal hatchery; wild ratio on the spawning grounds?, can modifications of hatchery environments reduce the deleterious genetic differences between hatchery and wild fish?,...

Project start year   1991    End year   2002

Start of operation and/or maintenance   

Project development phase   Implementation/Maintenance

Section 2. Narrative

Related projects
89 096 (A genetic monitoring and evaluation program for supplemented populations of salmon and steelhead in the Snake River basin)--Project 89-096 monitors the frequencies of (nearly) selectively neutral alleles (allozymes), in part, to estimate the reproductive success of hatchery fish used in supplementation programs. Study 90-052 handsomely complements 89-096 by providing information about the effect of such reproductive success on the fitness (or health), production, and productivity of the population of naturally spawning fish.

89-098 (Salmon supplementation studies in Idaho rivers)--Project 89-098 evaluates the success of ongoing supplementation programs for chinook salmon. Because long-term effects, although potentially very serious, may not begin to be discernable for at least eight or nine generations (30+ years; after Reisenbichler, in press), project 89-098 will be focussed on the short-term effects for the first several decades. Study 90-052 complements 89-098 by dealing with an additional species (steelhead), by evaluating genetic differences between hatchery and wild fish which allow extrapolation to both the short-term and long-term consequences of supplementation, and by testing for the feasibility of modifying hatchery programs to reduce genetic problems associated with supplementation.

90-055 (Steelhead supplementation studies in Idaho rivers)--Project 90-055 is to describe life history features of wild steelhead populations in Idaho. The weir that we designed and built under Project 90-052 for Fish Creek, Clearwater River system, is now being used for Project 90-055. The weir and the data that we collected with it during the first two years of this study are proving to be a cornerstone for Project 90-055. Idaho Fish and Game personnel consider 90-052 as the desirable, sister study to 89-098 and 90-055.

Other supplementation studies underway in the Snake and mid-Columbia river systems --These studies are funded by various agencies, and are similar to 89-098. Study 90-052 complements these studies in the same ways that it complements 89-098 or 90-055. Study 90-052 is the only one among these studies that allows specific evaluation of genetic differences between hatchery and wild fish, and excludes confounding with behavioral, physiological, or other direct effects of the hatchery programs.

Project history
We selected study streams and began experimentation to test for genetic differences in growth and survival of juvenile steelhead from hatchery and wild parents. Adult wild steelhead were captured from the Lochsa or Selway rivers and adult hatchery steelhead from Dworshak National Fish Hatchery in 1992, 1993, 1994, and 1995. These fish were used to make the desired experimental crosses. Comparisons of growth and survival for offspring of hatchery and wild fish are ongoing for three of the four year-classes in natural streams and at hatcheries. The validity of work with the fourth year-class (1993) was severely compromised by a lightning storm and resulting loss of flows to our incubators at Dworshak Hatchery which differentially affected the two experimental groups of fish, so we require work on one more year-class for this objective. Because of low run sizes, wild adult spring chinook salmon from the Warm Springs River were available to us only in 1992, but should be available again in 1996. Offspring of hatchery and wild spring chinook from the 1992 brood-year were compared for growth and survival in the hatchery, and were marked and released for comparison of subsequent growth and survival.

Cost sharing has occurred with U.S. Fish and Wildlife Service (USFWS) and subsequently with National Biological Service. These agencies have contributed $25,000-35,000 per year, or approximately 10% of the operating costs. The study also involves extensive cooperation or collaboration with many agencies and facilities including Confederated Tribes of the Warm Springs Reservation, Idaho Department of Fish and Game, Nez Perce Tribe, Oregon Department of Fish and Wildlife, USFWS (Idaho and Lower Columbia River Fisheries Resources Offices; Carson, Warm Springs, and Dworshak National Fish Hatcheries), U.S. Forest Service, and Washington Department of Fish and Wildlife.

Biological results achieved
Preliminary results for steelhead show that offspring of hatchery fish have lower fitness for natural rearing and higher fitness for hatchery rearing than do offspring of wild fish, demonstrating that domestication selection largely is responsible for these genetic differences. Preliminary results for spring chinook salmon indicate a different situation. Offspring of wild spring chinook salmon survived the same but grew faster in the hatchery than did offspring of hatchery fish, suggesting that relaxed selection, not domestication selection, may cause much of the genetic difference between hatchery and wild fish. Results from the 1996 and future year-classes are necessary to validate and expand the results from the 1992 year-class.

Annual reports and technical papers
-Annual report for 1992.
-Annual report for 1993 (in preparation).
-Reisenbichler, R.R., and G.S. Brown. 1995. Is Genetic Change From Hatchery Rearing of Anadromous Fish Really a Problem? Pages 578-579 in Uses and Effects of Cultured Fishes in Aquatic Ecosystems. American Fisheries Society Symposium 15. Bethesda, MD.
-Reisenbichler, R.R. (in press). Genetic factors contributing to declines of anadromous salmonids in the Pacific Northwest. Pages xx in D. Stouder and R. Naiman [eds.] Pacific Salmon and Their Ecosystems. Chapman & Hall, Inc.
-Reisenbichler, R.R. (in press; a). Questions and partial answers about supplementation--genetic differences between hatchery and wild fish. In Proceedings of the Columbia River Anadromous Salmonid Rehabilitation Symposium, Richland, WA (June 1995).
-Reisenbichler, R.R. (in press; b). Effects of supplementation with hatchery fish on carrying capacity and productivity of naturally spawning populations of steelhead. In Proceedings of the Workshop on Ecological Carrying Capacity for Columbia Basin Salmon Habitats. Bonneville Power Administration, Portland, OR (September 1995).

Management implications
Preliminary results for steelhead suggest that domestication selection, not relaxed selection, is the primary cause of reduced fitness for natural rearing, therefore (as yet undetermined) modifications of hatchery programs may substantially reduce the loss of fitness for natural rearing. Results from this study, in conjunction with data from two other studies, have provided a basis for estimating the efficacy of supplementation programs for steelhead, and suggest that the actual benefit (adult production) from supplementation programs may be only a fraction of that expected without considering genetic changes from hatchery rearing (Reisenbichler, in press, b). Where hatchery fish could be managed separately from wild fish--avoiding problems from mixed-stock fisheries, competition, predation, interbreeding, etc.--total production should be substantially higher by not supplementing, using the hatchery instead for a traditional production or harvest augmentation program. Even though our results to date are preliminary, they are sufficient to demand caution and to identify the imprudence of universally using supplementation to increase salmon and steelhead production.

Specific measureable objectives
Objective I.1.a: Compare the growth and survival of genetically marked offspring from wild steelhead (W) and from Dworshak Hatchery steelhead (H) rearing together in two natural streams in the Clearwater River system, Idaho. Comparisons of HxH and WxW fish will be completed for each of four year-classes. Growth (in length and weight) and survival will be evaluated at the end of each growing season, and at the time of downstream migration.

Objective I.1.b: Compare the growth and survival of genetically marked offspring from wild spring chinook salmon (W) and from Warm Springs Hatchery fish (H) in two natural streams in or near the Deschutes River system, Oregon. Comparisons of HxH and WxW fish will be completed for each of four year-classes. Growth (in length and weight) and survival will be evaluated at the end of each growing season, and at the time of downstream migration.

Objective I.2: Compare the growth and survival of genetically marked offspring from local wild fish (W) and from hatchery fish (H) in hatchery ponds at Dworshak, Clearwater, and Warm Springs hatcheries. Comparisons of HxH and WxW fish will be completed for each of four year-classes. The two groups of fish will be reared together (i.e., in the same ponds). Growth (in length and weight) and relative survival will be evaluated immediately before the juvenile fish are released from the hatchery as smolts. Steelhead will be reared at Dworshak and Clearwater hatcheries; spring chinook salmon will be reared at Warm Springs National Fish Hatchery.

Objective I.3 : Compare the reproductive success (the number of offspring produced) of genetically marked adult offspring from wild steelhead (WxW) and from hatchery steelhead (HxH) spawning in Silver Creek, South Fork Clearwater River system. The comparison is to be made for each of four year-classes.

Objective I.4 : Test for selection on the genetic marks by comparing the growth and survival of juvenile fish with the different genotypes rearing together in natural streams and in hatcheries. The test fish will be the offspring of hatchery fish. The tests will be repeated for up to four year-classes, depending on preliminary results from the first two year-classes.

Testable hypothesis
Hypothesis I.1.1. Survival in natural streams, from release to the end of each growing season and to downstream migration, does not differ among juveniles resulting from matings of HxH and WxW fish.

Hypothesis I.1.2. Growth in natural streams, from release to the end of each growing season and to downstream migration, does not differ among juveniles resulting from matings of HxH and WxW fish.

Hypothesis I.2.1. Survival in the hatchery, from fertilization to the standard time of release at each station and to returning adult, does not differ among fish resulting from matings of HxH and WxW adults.

Hypothesis I.2.2. Growth in the hatchery, from fertilization to the standard time of release at each station and to returning adults, does not differ among fish resulting from matings of HxH and WxW adults.

Hypothesis I.3.1. Reproductive success to swim-up fry is the same for offspring of HxH fish and WxW fish.

Hypothesis I.3.2. Survival from swim-up fry to fingerling in late August and from swim-up fry to smolt is the same for offspring of HxH fish and WxW fish.

Hypothesis I.3.3. Growth to late August is the same for offspring of HxH fish and WxW fish.

Hypothesis I.3.4. Size of smolts and timing of downstream (smolt) migration in the spring is the same for offspring of HxH fish and WxW fish.

Hypothesis I.4.1. Survival of juvenile fish from release to the end of the first summer (chinook salmon) or second summer (steelhead) in natural streams is independent of their genetic mark.

Hypothesis I.4.2. Growth of juvenile fish to the end of the first summer (chinook salmon) or second summer (steelhead) in natural streams is independent of their genetic mark.

Hypothesis I.4.3. Survival of juvenile fish in the hatchery and in a natural stream from fertilization to the time of release or migration as smolts is independent of their genetic mark.

Hypothesis I.4.4. Growth of juvenile fish in the hatchery and in a natural stream to the time of release or migration as smolts is independent of their genetic mark.

Underlying assumptions or critical constraints
Adequate numbers of returning adults must be available from wild populations and hatchery populations for us to initiate each complete replicate (year-class). These numbers may vary from year to year, and are determined, in consultation with us, by the Confederated Tribes of the Warm Springs Reservation (hatchery and wild spring chinook salmon), Idaho Department of Fish and Game and Perce Tribe (wild steelhead), and U.S. Fish and Wildlife Service (hatchery steelhead and spring chinook salmon). Barring too few fish, lightning strikes, or other "Acts of God," the study can proceed.

Methods
The experimental design uses genetic marks so that experimental groups of fish can be released as eyed embryos or swim-up fry (not easily marked by other means) to rear together in the same stream or hatchery pond. Genetic marks also enable tests of reproductive success where the experimental fish result from natural spawning of (genetically marked) hatchery and wild adults in the same stream (hence, no opportunity to handle the offspring and apply a physical mark). Mixing experimental fish and introducing them to the streams as eyed-embryos or swim-up fry avoids or severely restricts the influences of the hatchery environment that might confound our comparisons between groups of fish. When experimental organisms share a common environment for their entire life, any differences between them illustrate genetic differences (or maternal effects).

Genotypes at the dipeptidase locus serve as the genetic marks for steelhead, and at the superoxide dismutase locus for spring chinook salmon. Each year, wild adult fish are captured, and a small sample of muscle tissue is extracted from each adult. The genotype is determined from each tissue sample with horizontal starch-gel electrophoresis, and all fish are released except those homozygous for the common allele, keeping 25 males and 25 females. Adult hatchery fish are captured at the respective hatchery, and are similarly screened for the appropriate (alternate) genotypes. At least 25 of each sex are retained for the study. Adults with the appropriate genotypes are held until mature, at which time they are spawned in 2x2 crosses, if possible, to ensure substantial genotypic variation (Objectives 1.1 & 1.2), or they are radio-tagged and released into the study stream to spawn naturally (Objective 1.3). Each study stream receives at least 20,000 fry for Objective I.1, representing all families from each experimental group; each hatchery pond (Objective I.2) receives at least 3300 from each experimental group.

We test to ensure that the experimental crosses have the correct genotypes by holding 5 to 10 embryos from each mating, rearing them to hatching or button-up, then sacrificing them and verifying the genotypes. We test for possible maternal effects confounding comparisons of HxH and WxW fish by making HxW crosses using only hatchery females and wild males--if differences between HxH and WxW fish are due to maternal effects rather than genetic effects, the performance of HxW fish should be indistinguishable from that of HxH fish; otherwise, genetic differences are indicated. Egg size is measured volumetrically or by subsampling individual eggs. Mean egg size is determined for hatchery fish and for wild fish.

Samples of approximately 250 experimental fish are collected from each study stream by electrofishing or seining in late summer each year, and as fall or spring outmigrants in downstream migrant traps. Differences in abundance are tested by chi-square or log-likelihood analysis. Differences in size (growth) are tested with one-way ANOVA.

Brief schedule of activities
The original study plan approved for this study gives a detailed schedule for each of the 24 primary tasks. Here I provide a brief summary.
1997--
Implement Objectives for the 1997 year-class of steelhead by collecting adult wild and hatchery fish in Idaho's Clearwater River system, assaying genotypes, making the experimental crosses, and releasing experimental fish in natural streams and hatchery ponds. Continue Objectives I.1, I.2, & 1.4 for previous year-classes by collecting juvenile fish from study streams and trapping downstream migrants, and by sampling adult experimental fish returning to Dworshak National Fish Hatchery. Analyze data, prepare progress reports, and prepare manuscripts for publication.

Implement Objectives for the 1997 year-class of spring chinook salmon by collecting adult wild and hatchery fish in Oregon's Deschutes River system, assaying genotypes, making the experimental crosses, and releasing experimental fish in natural streams and hatchery ponds. Continue Objectives I.1, I.2, & 1.4 for previous year-classes by sampling adult experimental fish returning to Warm Springs and Carson National Fish Hatcheries. Analyze data, prepare progress reports, and prepare manuscripts for publication.

1998-2001
Objective I.3 is initiated in 1998, and releases of adult fish continue for three years. Objectives I.1, I.2, & I.4 are completed for steelhead in 2000. These objectives are continued for spring chinook salmon with releases of experimental fish in 1998, 1999, and 2000.

Biological need
Some persons have identified supplementation as a tool of major importance for restoring the salmonid fisheries of the Columbia and Snake river systems. Other persons have identified supplementation as a major force compromising the sustainability and persistence of the endemic, naturally spawning (wild) stocks of salmonids. Much of the disagreement and confusion (and therefore lack of progress) with supplementation stems from our lack of solid information concerning the effects of supplementation, particularly the long-term or genetic effects on sustainability of wild populations. The purpose of study 90-052 is to provide such information to help in current planning and thinking, including the identification of important additional hypotheses to be tested. Even just the preliminary data from study 90-052, considered in conjunction with data from two previous studies, (arguably) provide a minimally sufficient data set for evaluating the long-term consequences of supplementing steelhead and provide a greatly improved basis for planning supplementation programs (Reisenbichler, in press, b). The data from this study will allow more complete consideration and analysis of questions such as whether or not to supplement rather than simply augment harvest?, what is the optimal capacity for a hatchery?, what is the optimal hatchery:wild ratio on the spawning grounds?, can modifications of hatchery environments reduce the deleterious genetic differences between hatchery and wild fish?, ...

As implied above, all of the data to test for and evaluate genetic differences in growth or survival between hatchery and wild salmonids come from steelhead. Chinook salmon have different habitat requirements and other life-history characteristics than do steelhead, so the genetic effects of hatchery rearing on fitness for natural rearing may be different than for steelhead. Our study will be the first to develop this important information for chinook salmon. Indeed our (very) preliminary results for spring chinook salmon suggest a substantially different response to hatchery rearing than for steelhead--relaxed selection, rather than domestication selection may the dominant factor operating in the hatchery environment. If this result persists for the one year-class being tested and holds for the remaining year-classes, it suggests that, unlike for steelhead, there is little potential for altering hatchery environments to ameliorate the loss of genetic fitness for natural rearing.

Critical uncertainties
We assume that the genetic marks are selectively neutral, that differences observed between experimental groups result from genetic differences not maternal effects, and that incubation at different temperatures doesn't differentially effect subsequent growth or survival of experimental fish. Results from other studies suggest that the first two assumptions are valid; however, we have included ancillary tests in our study to evaluate these assumptions for our particular circumstances.

Summary of expected outcome
We expect results that provide answers to the following questions relevant to supplementation and conservation biology:
1. Do additional comparisons of hatchery and wild steelhead support or contradict previous results indicating that hatchery populations are genetically less fit for rearing in natural streams than are populations of wild fish?
2. What is the expected magnitude of difference between hatchery and wild steelhead in fitness for natural rearing, and how does this vary for different sets of hatchery and wild populations?
3. How fast do genetic differences between hatchery fish and wild fish develop, and what is the progression through time? (Answered in conjunction with data from previous studies.)
4. How much of the difference in reproductive success between hatchery fish and wild fish is due to differences in time of spawning and other aspects of spawning behavior rather than differences in survivability?
5. Are genetic differences between hatchery fish and wild fish different (greater?) for steelhead (the only species directly evaluated to date) than for spring chinook salmon?
6. Have previous attempts at steelhead supplementation or recolonization in the South Fork Clearwater River failed because an unsuitable source stock (Dworshak Hatchery stock) was used?
7. How great is the benefit to population restoration from using wild fish as broodstock? (Is the benefit worth the cost of depleting wild populations?)
8. Does genetic adaptation to hatchery conditions (in contrast to relaxed selection in the hatchery) account for a substantial portion of the genetic difference between hatchery fish and wild fish? (If so, it is likely that hatchery environments or practices can be altered to reduce domestication.)
9. Can genetic differences between hatchery fish and wild fish be substantially reduced by developing the hatchery stock from local wild fish, and including wild fish in the brood stock each year while avoiding selective breeding in the hatchery for nonadaptive traits (such as large body size or early time of spawning)?

Dependencies/opportunities for cooperation
Various forms of cooperation, collaboration, or assistance from the Confederated Tribes of the Warm Springs Reservation, Idaho Department of Fish and Game, Nez Perce Tribe, Oregon Department of Fish and Wildlife, U.S. Fish and Wildlife Service, U.S. Forest Service, and Washington Department of Fish and Wildlife have helped or been integral to the success of this project. Relations with each of these entities are good, and should remain so. Lack of enough returning adults to allow full implementation with a year-class can reduce the costs for that year, and if BPA and NPPC choose, increase the duration of the study.

Risks
Risks to the safety and health of personnel are modest, and no greater for this study than for most field studies in fisheries. We minimize impacts to the source populations of fish by appropriating only a small fraction of each population; integrating our study with existing programs as much as possible; and either differentially marking our experimental fish for later separation from source populations, or releasing experimental fish where they will not mix with the source populations.

Monitoring activity
This study is a designed experiment, where measurement of yield variables or outcomes is integral. See OBJECTIVES and HYPOTHESES above for more detail.

Section 3. Budget

* For most projects, Authorized is the amount recommended by CBFWA and the Council. Planned is amount currently allocated. Contracted is the amount obligated to date of printout.

Funding recommendations

CBFWA funding review group   System Policy

Recommendation    Tier 1 - fund

Recommended funding level   $444,000

BPA 1997 authorized budget (approved start-of-year budget)   $444,000