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
Ecology of the American Shad in the Impounded Lower Columbia River

BPA project number   5509000

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   , EWN

Biological opinion ID   Immediate Actions to Improve Survival, 13.h, 14

NWPPC Program number   5.7A.2, 5.7B.9

Short description
The increasing abundance of adult and juvenile American shad in the Columbia River basin has prompted concerns about their potential impacts on dwindling salmonid populations. Despite this little is known about shad biology in impounded reaches of the Columbia River. This lack of information is recognized in both the National Marine Fisheries Service’s Biological Opinion and the Proposed Recovery Plan, Recover Task 2.8.b.2 and 2.8.b.3. We propose to study the spawning and rearing biology of American shad in the John Day Pool to elucidate factors that may be responsible for variations in shad year-class strength. We will study the early life stages because an investigation of Connecticut River shad populations suggested that year-class strength was determined during egg or larval stages (Crecco et al. 1983). Our study will also examine the interactions between juvenile American shad and juvenile fall chinook salmon. Specifically, we will examine the role of American shad larvae as food items for juvenile fall chinook salmon and the potential for competition between juvenile shad and juvenile fall chinook salmon. In addition, we will determine the role of shad as an abundant prey species that enables predators such as northern squawfish Ptychocheilus oregonensis to increase late fall condition factors thereby increasing fecundity and overwinter survival.

Project start year   1997    End year   2001

Start of operation and/or maintenance   0

Project development phase   Implementation

Section 2. Narrative

Related projects
BPA 8200300 and 9007800 - Predation studies: Extensive data sets are available to assist in evaluating the relative role of shad to predator growth and survival.

BPA 9102900 - Fall chinook salmon studies: This study can provide information on nearshore and offshore distribution patterns of fall chinook relative to water velocities in McNary and John Day Reservoirs.

Project history

Biological results achieved

Annual reports and technical papers

Management implications

Specific measureable objectives
Our objectives are to: 1)identify determinants of variation (e.g. temperature and flow regimes, zooplankton abundance, escapement of adult shad) in juvenile abundance and year class strength; 2) quantify shad interactions with juvenile fall chinook salmon, and 3) determine the extent to which availability of juvenile American shad may increase growth and fecundity of predators.

Testable hypothesis
(Ho) There is no relation between factors such as temperature and flow regimes on annual abundance of juvenile American shad. (Ho) There is no relation between food and growth of American shad and juvenile chinook salmon. (Ho) American shad as a dietary component have no effect on growth and fecundity of predators.

Underlying assumptions or critical constraints
1) Endangered Snake River fall chinook salmon migrate through the lower Columbia River reservoirs during late summer.
2) Abundance of American shad and juvenile fall chinook salmon do not collapse due to factors outside of the reservoir environment.
3) Using state of the art methods we will be able to quantify the role of juvenile shad as prey or competitor of fall chinook salmon.
4) A representative range of flow conditions will be available during the study.
5) Valid inferences can be drawn from known aspects of shad ecology on the East coast of the U.S.

Methods
The study will be conducted in lower Columbia River reservoirs, emphasizing the John Day reservoir. The reservoir will be stratified into sampling segments based on macrohabitat type. American shad eggs and larvae will be sampled biweekly using 0.5 m2 plankton nets (500 mm mesh). Late summer indices of juvenile abundance will be estimated using beach seines in shallow nearshore habitats and a hydroacoustic fish stock assessment system in limnetic areas. To determine if juvenile shad are a prey and/or competitor with juvenile fall chinook salmon we will assess spatial and temporal distribution patterns and diet overlap. These data will be used in a bioenergetics model to assess potential interactions. The contribution of juvenile American shad to seasonal growth and fecundity of predators will be estimated using techniques developed by Oregon Department of Fish and Wildlife and the National Biological Service during predation studies. Variables such as temperature, depth, turbidity, and water velocity will be measured concurrently with fish sampling at each collection site. Statistical analyses will include correlative approaches for exploring relationships between shad densities and other variables and ANOVAs for between or among habitat or year differences in shad densities.

Brief schedule of activities
FY 1997: We propose to complete detailed study protocols and synthesize existing shad data collected incidental to previous studies in the John Day Pool. Conduct preliminary field sampling.

FY 1998-2001 Conduct field sampling to meet all objectives.

Biological need
Basic information on American shad reproduction and early life history in the Columbia River is essential for effective management of shad populations and evaluation of shad-salmonid interactions. This need was recognized in the Biological Opinion; The Recovery Plan 2.8, "Reduce loss of listed fish to predators and competitors"; and the Council's Fish and Wildlife Program 5.7.A.2, "Explore the population ecology of shad .......".

Critical uncertainties
Currently, there is little basic biological information on the importance of American shad to the overall ecology of the Columbia River basin. Impoundments created by hydroelectric development have apparently bolstered shad populations. The impacts of expanding shad populations on dwindling salmonid stocks are largely unknown. Obtaining basic life history information on American shad and interactions with juvenile chinook salmon is an initial step critical to understanding their overall role in the Columbia River environment.

Summary of expected outcome
1) Year class strength of American shad is expected to be determined by natural variation in environmental variables or by variation in variables related to hydrosystem operation.
2) American shad are expected to have two interactions with juvenile fall chinook salmon: 1) as prey in the larval form, 2) as a competitors when biomass of juvenile shad increases in late summer while endangered fall chinook salmon from the Snake River are still likely to be present.
3) American shad are expected to contribute significantly to energy intake by northern squawfish.

Dependencies/opportunities for cooperation
Oregon Department of Fish and Wildlife will be a collaborator on the predator relations.

Some of the proposed activities will require ESA permits and state fish collection permits.

Risks
We believe that the proposed sampling activities will not jeopardize salmon stocks.
The NBS and Oregon Department of Fish and Wildlife have excellent safety records.

Monitoring activity
1) The project will prepare annual reports that will be available for peer review.
2) The project will submit a Statement of Work for review by interested parties, fisheries agencies, and the Tribes.
3) The project will prepare and submit papers for peer review and publication in journals or procedings of symposia.

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 2 - fund when funds available

Recommended funding level   $450,000