200751700 - Estimating abundance of white sturgeon by using visual strip-transects; an alternative to mark-recapture population estimates

Sponsor: US Geological Survey - Cook

Short description: We will determine if acoustic imaging technologies and visual strip-transect abundance estimation techniques can be used to estimate numbers of white sturgeon present in river reaches. This would add value to ongoing sturgeon stock assessment activities.

Location: Mainstem/Systemwide province, Columbia Gorge subbasin

Budgets: FY08: $344,027 | FY09: $246,898

Primary species:
Resident: White Sturgeon: All Populations

Objectives

ObjectiveDescriptionSubbasin planStrategies
1. Estimate numbers of white sturgeon All sturgeon restoration and management activities need to know how many sturgeon are present within a given river reach. We will develop a visual strip-transect sampling strategy that should provide the basis for deriving estimates of sturgeon abundance without using mark-recapture techniques. We will employ acoustic imaging technologies including side scan sonar or acoustic cameras to image areas of the riverbed. A well- designed stratified random sampling approach and allocation of efforts among strata should enable us to estimate abundance of white sturgeon. Pilot studies will have to be done to assess accuracy and precision of the visual strip-transect approach. Columbia Gorge Manage white sturgeon in Bonneville Reservoir for sustainable harvest.
2. Improve management of white sturgeon fisheries Management of white sturgeon populations requires accurate estimates of numbers of fish present. Current mark-recapture population estimation techniques suffer from biases associated with capture efficiency and gear selectivity. Sidescan sonar imagery can be used to make visual counts of the numbers of larger fish present along transects. These counts, coupled with a well-planned sidescan sonar survey, can provide a separate estimate of abundance. This estimate can be used to either validate mark-recapture estimates or it could be used instead of mark recapture estimates. Lower Columbia Manage Columbia River fisheries at sustainable levels, maintaining viable populations through consistent recruitment to adulthood and adequate spawner abundance.

Narrative

Recommendations

  • ISRP: Unranked
  • Council: Not fundable
  • BPA: Not fundable