2023 Fraser River sockeye escapement assessment plan

The Fraser River Sockeye Stock Assessment Program has a mandate to provide reliable escapement estimates for all Fraser River Sockeye populations. Individual populations are assessed using standard assessment methods, with the choice of method determined by the number of spawners expected to return by population. High precision methods such as enumeration fences, hydroacoustic (DIDSON or ARIS SONAR) and mark-recapture assessments are used for populations with expected escapements exceeding 75,000, and visual surveys are used for populations with expected escapements of less than 75,000. High precision are also used in place of visual surveys in systems that are poorly suited to the latter. The 2023 plan is as follows:^{Footnote 1}:

• Mark-recapture studies: Mark-recapture studies are planned for the Harrison River (Summer Run).
  
• Enumeration fences: Fences are planned for the Scotch Creek (Early Summer Run) and Cultus Lake (Late Run) populations.
• Hydroacoustic: SONAR projects are planned for the Nadina and Taseko (Early Summer Run); Quesnel, Chilko and Stellako (Summer Run); and Birkenhead (Late Run) populations.
• Visual surveys: Cyclic visual surveys by foot, boat or helicopter are planned for all remaining Fraser Sockeye populations.

2023 Fraser river sockeye escapement reporting

Preliminary estimates are based on data that have been entered into the computer database at the completion of the field project. Data accuracy has not been verified and bias tests have not been performed (e.g., mark-recapture studies). Significant changes in preliminary estimates are possible. The anticipated release schedule for Preliminary estimates is: Early Run (Stuart) in early November; Early Summer Run in early December; Summer Run in early January; and Late Run in early February 2024.

Near Final estimates are based on data that have been verified for accuracy, tested for bias and corrected for age composition (adults vs. jacks). Changes in near final estimates are unlikely. Near Final estimates will be available for all run groups in March 2024.

Contact us

Sean Everitt
Email: Sean.Everitt@dfo-mpo.gc.ca
Telephone: 250-299-1310