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
Supplementation Fish Quality (Yakima)

BPA project number   9105500

Business name of agency, institution or organization requesting funding
NMFS

Sponsor type   WA-Federal Agency

Proposal contact person or principal investigator

BPA technical contact   Jodi Stroklund, EWN 503/230-4512

Biological opinion ID   None

NWPPC Program number   7.4K.1

Short description
Define criteria for setting quality of hatchery fish for supplementation.

Project start year   1991    End year   

Start of operation and/or maintenance   

Project development phase   Implementation

Section 2. Narrative

Related projects
The Supplemental Fish Quality Project is developing and refining fish rearing strategies to be tested in the planned BPA Yakima Fisheries Project test of supplementation. To our knowledge, project numbers have not been assigned to individual components of the proposed test. The scope of proposed tests are described in the Environmental Impact Statement for the Yakima Fisheries Project (DOE/EIS-0169).

Project history
The Coastal Zone and Estuarine Studies Division, National Marine Fisheries Service, in collaboration with the Washington Department of Fish and Wildlife, has been conducting research to develop a natural rearing enhancement system (NATURES) suitable for producing "wild-like" fish from hatcheries. NATURES research is currently directed at providing guidelines for the Yakima Fisheries Project test of supplementation. However, NATURES has application to restoration of many depleted stocks of fish in the Snake River Basin (e.g., those listed under the U.S. Endangered Species Act). Development of natural rearing systems that minimize behavioral changes in hatchery-reared fish is identified as a priority [4.4.d] in the proposed Recovery Plan for Snake River salmon.
Hatchery practices that induce domestication are considered prime factors in reducing fitness of hatchery fish for subsistence in natural ecosystems. Present hatchery practices are geared toward mass-production under unnatural conditions (e.g., the fish are reared in the open, over uniform concrete substrate; provided no structures behind or under which to seek refuge from water current, predators, or dominant conspecifics; held at high stress-producing densities; surface fed; and conditioned to approach large moving objects at the surface). It is probable that physiological, behavioral, and morphological modifications resulting from this unnatural rearing environment are major factors in the poor post-release survival of many standard hatchery-reared salmon.
NATURES strategies for salmonids include rearing fish in raceways equipped with cover, structure, and natural substrates that promote development of proper body camouflage coloration, feed delivery systems that condition fish to orient to the bottom rather than the surface of the rearing vessel, training fish to avoid predators, exercising fish to enhance their ability to escape from predators, supplementing diets with natural live foods to improve foraging ability, reducing rearing densities, and utilizing oxygen-supplementation technology.
NATURES strategies should provide "wild-like" fish from hatcheries that are more suitable for use in supplementation programs than conventionally-reared fish. NATURES strategies also should help minimize potential genetic divergence between wild and hatchery-reared salmonids.
Initial studies have demonstrated that NATURES strategies have the potential to increase post-release survival of hatchery-reared salmonids by 50% or more compared to conventional rearing methods.

Biological results achieved
Research has shown that both the unintended selection and conditioning associated with standard artificial propagation practices generally produces salmonids that are less adept at foraging, less cryptic, more vulnerable to predators, and differ in their level of aggression compared to their wild counterparts. We have evaluated the effectiveness of various NATURES concepts in three post-release survival experiments conducted on chinook salmon (Oncorhynchus tshawytscha). The NATURES habitats tested in 1992-1994 increased the instream postrelease survival of juvenile chinook salmon by 25-50%.

In the first experiment, fall chinook salmon reared for 4 months from swim-up to smoltification in 400-l raceways with cover, structure, and substrate experienced about 50% better in-stream survival to a collection weir 2.2 km downstream than conventionally-reared controls. In a second experiment, spring chinook salmon reared in similar 400-l raceways for the last 3 months prior to smoltification exhibited about 25% greater post-release survival to a collection weir 225 km downstream than controls in clear water conditions. However, in turbid water conditions there was no significant difference in post-release survival between test and control groups. In the final experiment, fall chinook salmon reared for 4 months from swim-up to smoltification in 5,947-l raceways with cover, structure, substrate, and subsurface feeding systems experienced about 25% better post-release survival to a collection weir 21 km downstream than conventionally-reared controls.

Annual reports and technical papers
Maynard, D. J., T. A. Flagg, and C. V. W. Mahnken. 1995. A review of semi-natural culture strategies for enhancing the postrelease survival of anadromous salmonids. Am. Fish. Soc. Symp. 15:307-314.

Maynard, D. J., G. C. McDowell, E. P. Tezak, and T. A. Flagg. In press. The effectiveness of live-food supplementation in improving the foraging ability of fall chinook salmon. Submitted to Prog. Fish-Cult., October 1995.

Maynard, D. J., T. A. Flagg, and C. V. W. Mahnken, and S. L. Schroder. In press. Natural rearing technologies for increasing postrelease survival of hatchery-reared salmon. In Proceedings of the 1994 U.S./Japan Natural resources meeting on aquaculture, Ise, Japan. 20 p. Scheduled for publication in Spring 1996.

Maynard, D. J., T. A. Flagg, and C. V. W. Mahnken. In prep. Development of a natural rearing system to improve supplemental fish quality. Report to the Bonneville Power Administration, Contract DE-A179-91BP20651, approx 200 p. (Available Northwest Fisheries Science Center., 2725 Montlake Blvd. E., Seattle, WA 98112.)

Management implications
The goal of supplementation and conservation programs for threatened and endangered stocks is to develop methods to enhance populations by supplementing wild stocks with hatchery fish. The use of hatchery fish to supplement native populations holds good potential for recovery of natural populations, but existing techniques are controversial. NATURES research is a critical step in determining how live food diets, automated subsurface feeders, and seminatural rearing habitat may increase the postrelease survival of hatchery salmonids. Predation experiments will also help to demonstrate whether predation is a significant factor in the differential postrelease survival of test fish. These studies will help to define rearing environment factors critical to improving postrelease survival of fish released for supplementation.

Specific measureable objectives
Develop and refine NATURES rearing strategies. Compare NATURES-reared fish with conventionally- and naturally-reared fish.

Testable hypothesis
The research is examining the hypothesis that rearing salmon in raceways equipped with overhead cover, natural substrate, instream structure, and subsurface feed delivery systems and employing the use of live natural foods, exercise, and predator avoidance training will significantly increase postrelease survival compared to conventionally-reared fish.

Underlying assumptions or critical constraints
Full-scale raceway studies must be initiated in future years to determine if increased juvenile postrelease survival demonstrated in NATURES rearing studies translates into enhanced adult survival.

Methods
Research in 1997 will focus on refining NATURES variables and examining ecological interactions between conventionally-, NATURES-, and wild-reared fish. This includes:

1. Rearing fish in replicated groups using conventional fish culture methods and using NATURES methods where rearing vessels are equipped with overhead cover, natural substrate, instream structure, and subsurface feed delivery systems. Fish will be reared in freshwater to smolting and released. A number of different studies will be conducted. Depending on the exact study, rearing vessel size may range from 400-l to 40,000-l.

2. Appropriate bioassays and statistical analysis will be conducted to compare behavioral differences, predator susceptibility, and ecological interactions of NATURES- and conventionally-reared fish at pre- and post- release stages.

3. A number of different NATURES rearing habitat studies will be conducted. Most studies will be conducted using chinook and coho salmon. Depending on the exact study, number of fish per study may range from 1,000 to 60,000.

Brief schedule of activities
1997: Conduct experiments to refine NATURES variables. Release juveniles and assess survival. Examine interactions between conventionally-, NATURES-, and wild-reared fish. Including;

1. Fall 1996-spring 1997 - establish conventional and NATURES rearing units. Rear fish and conduct prerelease bioassays including predator susceptibility, foraging efficiency, and social interactions.

2. Spring-summer 1997 - Release replicated groups of conventionally- and NATURES-reared fish. Conduct instream bioassays including predator susceptibility, foraging efficiency, and social interactions. Evaluate ecological interactions between NATURES-, conventionally-, and wild-reared fish. Recapture juveniles at stream weirs and compare instream survival.
3. Write reports and scientific papers.

Similar project activities are expected in 1998-2001, except that beginning in 1998, work elements may also include quantifying adult survival of test and control fish.

Biological need
In the recent National Research Council (NRC) report “Upstream - salmon and society in the Pacific Northwest” the authors noted that “physical and biological conditions in hatchery facilities have differed greatly from those in natural environments and in general have lacked diversity in habitat structure, cover, and exposure to natural predators”. Furthermore, they stated that “the hatchery rearing environment has the potential to alter selection pressures in a single generation, decreasing fitness in the natural environment”. The successful use of hatcheries in the recovery process for endangered populations depends on developing new NATURES-like rearing technologies that help hatchery fish retain innate wild attributes. Development of this conservation hatchery strategy is a high priority project identified as critical in the NMFS Proposed Endangered Species Act (ESA) Recovery Plan for Snake River sockeye and chinook salmon (Sections 4.4c and 4.4d). Development of strategies to increase postrelease survival of hatchery fish are also called for in the Northwest Power Planning Council’s Columbia Basin Fish and Wildlife Program (Section 700e). The development of NATURES fish rearing strategies supports the planned BPA Yakima Fisheries Project test of supplementation as described in the Environmental Impact Statement for the Yakima Fisheries Project (DOE/EIS-0169).

Critical uncertainties
Whether NATURES rearing strategies can produce hatchery-reared fish with similar behavior and survival as wild fish.

Summary of expected outcome
The goal of supplementation and conservation programs for threatened and endangered stocks is to develop methods to enhance populations by supplementing wild stocks with hatchery fish. The use of hatchery fish to supplement native populations holds good potential for recovery of natural populations, but existing techniques are controversial. NATURES research is a critical step in determining how live food diets, automated subsurface feeders, and seminatural rearing habitat may increase the postrelease survival of hatchery salmonids. Predation experiments will also help to demonstrate whether predation is a significant factor in the differential postrelease survival of test fish. These studies will help to define rearing environment factors critical to improving postrelease survival of fish released for supplementation. NATURES studies will provide precision for fish rearing strategies to be used in the planned BPA Yakima Fisheries Project test of supplementation as described in the Environmental Impact Statement for the Yakima Fisheries Project (DOE/EIS-0169).

Dependencies/opportunities for cooperation
NMFS is cooperating with the Washington Department of Fish and Wildlife (WDFW) in conducting NATURES research. Continued NMFS/WDFW cooperative research is critical to the success of refining NATURES rearing variables and conducting juvenile and adult survival evaluations.

Risks
No known critical risks are associated with studies to develop conservation hatchery strategies for producing wild-like fish for use in supplementation projects.

Monitoring activity
Survival evaluations of fish reared under NATURES strategies will be measured at the juvenile and adult stage. Juveniles will be collected at weirs during year(s) of outmigtation. Adults will be collected at traps and from spawning grounds and this data used in conjunction with fishery tag returns to assess the effect of the rearing treatments on smolt-to-adult survival.

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   Bonneville Dam - Priest Rapids Dam

Recommendation    Tier 1 - fund

Recommended funding level   $400,000

BPA 1997 authorized budget (approved start-of-year budget)   $400,000