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
Northern Squawfish Management Program

BPA project number   9007700

Business name of agency, institution or organization requesting funding
PSMFC

Sponsor type   PSMFC

Proposal contact person or principal investigator

BPA technical contact   Bill Maslen, EWI 503/230-5549

Biological opinion ID   NMFS BO RPA Sec. 14

NWPPC Program number   5.7B.1

Short description
Implement squawfish management program to reach predation control goals; evaluate squawfish population response; improve survival at mainstem hydro facilities.

Project start year   1990    End year   

Start of operation and/or maintenance   1997

Project development phase   Implementation

Section 2. Narrative

Related projects
Projects related to flow augmentation, spill, and mechanical bypass achieve the same biological objective of improving downstream migrant survival.

Project history
1990: $1,421,813
1991: $5,259,629
1992: $6,846,410
1993: $4,253,600
1994: $3,670,708 + $600,000 reward contract
1995: $4,100,000

The purpose of the project is to test a hypothesis based on research in John Day Reservoir by ODFW from 1982 through 1988 that indicated through modeling simulations that a 10-20% exploitation rate on northern squawfish would result in up to a 50% reduction in predation on juvenile salmonids.

Biological results achieved
This project has removed over 977,000 predator-sized northern squawfish from the mainstem Columbia River since 1990 with 217,000 of those removed in 1995 for an exploitation rate of 15.6% in 1995. The projected reduction in predator caused juvenile salmonid mortality is estimated at 36% for 1996 when compared to pre-program levels. If harvest rates similar to 1995 continue, a 41% reduction in the consumption of juvenile salmonids by northern squawfish is estimated by 1998.

Annual reports and technical papers
Quarterly and annual reports available.

Management implications
The dam-angling fishery element of this project had demonstrated that northern squawfish numbers are greatly reduced in the powerhouse tailrace during periods of heavy spill most likely because of reduced prey abundance.

Specific measureable objectives
The overall objective is to reduce northern squawfish predation on juvenile salmonids by a sustained removal of 10-20% of the predator sized (11 inches or larger) northern squawfish annually.

Testable hypothesis
The testable hypothesis is that a sustained annual exploitation rate of 10-20% on northern squawfish will result in up to a 50% reduction in juvenile salmonid consumption by northern squawfish after 5 years of implementation.

Underlying assumptions or critical constraints
1. The 10-20% annual exploitation rate on northern squawfish can be maintained over the long term. 2. No significant compensation by either northern squawfish or other predator populations will occur.

Methods
Northern squawfish are being removed through a sport reward fishery, a dam-angling fishery and site specific (tributary mouth) gill-net fisheries. Evaluation is based on sustained exploitation rate and size composition of harvested northern squawfish and estimated reduction in predation on juvenile salmonids. This required information on changes in relative abundance, consumption, size and age structure, growth, and fecundity of northern squawfish in the mainstem Snake and Columbia rivers. Statistical analysis is conducted on all variables measured.

Brief schedule of activities
The plan for 1997 is to continue existing fisheries with reduced dam-angling effort because of expected high levels of spill which greatly reduced dam-angling effectiveness in 1995. Annual northern squawfish management activities will be altered, based on the ongoing evaluation, to meet program objectives and enhance program effectiveness. Long-term implementation of this program will be based on ongoing biological evaluations.

Biological need
The biological need is based on the results of eight years of research in John Day Reservoir which determined that reservoir mortality was caused primarily by predation and that northern squawfish were responsible for 80 % of all aquatic predation.

Critical uncertainties
The critical uncertainty is whether the desired 10-20% exploitation rate on northern squawfish can be maintained for the long term.

Summary of expected outcome
We believe that the exploitation rate achieved during 1995 (15.6%) can be sustained with the current funding level. This is projected to result in a sustained reduction in juvenile salmonid consumption by northern squawfish of 41%.

Dependencies/opportunities for cooperation
Requirements to increase the sustainable exploitation rate (such as the NPPC�s Fish and Wildlife Program�s requirement to exceed 20% exploitation rate) would substantially increase program costs. In the past, delays in the receipt of a biological opinion threatened our ability to tag numbers of northern squawfish needed to measure exploitation rates of the various fisheries.

Risks
All fisheries take both juvenile and adult salmonids listed as threatened or endangered and are constrained by the biological opinion.

Monitoring activity
Program evaluation is being conducted by ODFW and should be completed during FY96. A minimum level of monitoring activity is planned for subsequent years.

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   $4,000,000

BPA 1997 authorized budget (approved start-of-year budget)   $3,450,000