Terms of Reference

Assessment of and recommended sustainable harvest level for Dolly Varden from the Big Fish River, NT

Regional Peer Review - Central and Arctic Region

February 29, 2012
Winnipeg, Manitoba

Chairperson: Margaret Treble

Context

Anadromous Dolly Varden (Salvelinus malma) is important for the subsistence of Gwich’in and Inuvialuit peoples. Due to declines in abundance of Dolly Varden from the Big Fish River, NT all fishing activity was prohibited in the river proper, including its tributary, the Little Fish River, and areas adjacent to its mouth in the Mackenzie River Delta in 1987. Currently, Dolly Varden from the Big Fish River are only harvested in a mixed-stock-fishery along the Beaufort Sea coast, mainly at Shingle Point, YT. Subsequent assessments (2002 and 2008) have demonstrated that population abundance has remained low and it is unclear whether this is a result of harvesting, changes in overwintering habitat that may influence carrying capacity or a combination of both. Recent population studies and coastal harvest monitoring activities that include the collection of catch information and biological data, tissue samples for genetic analysis, and tag returns allows a more comprehensive assessment of the stock. The Aklavik Hunters and Trappers Committee has requested a limited harvest of Dolly Varden from the Big Fish River. As a result, Fisheries and Oceans Canada (DFO) Fisheries Management has requested science advice on the current stock status, particularly the population abundance estimate and sustainable harvest level of Dolly Varden from the Big Fish River.

Objectives

This advisory meeting is being held to undertake a science-based peer review of all available information relevant to providing advice on the population abundance estimate and sustainable harvest level for the Big Fish River Dolly Varden stock, including the following:

1. Evaluation and comparison of population estimation methods (mark-recapture and Dual Frequency Identification Sonar [DIDSON]) used in recent assessments (2009 and 2010)).
2. Comparison of contemporary population estimates with past results.
3. Comparison of contemporary biological information (length, sex, maturity, and growth) with past data collected at the spawning/overwintering site.
4. Examination of the contribution of Dolly Varden from the Big Fish River to the mixed-stock-fishery at Shingle Point using genetic mixed stock analysis and recent tag return information.
5. Evaluation of recent Dolly Varden harvest statistics from Shingle Point (2010 and 2011) in the context of the mixed stock fishery composition.
6. Evaluation of the sustainable harvest level and the associated risks for the stock.

Expected publications

All reports will be published on the Canadian Science Advisory Secretariat (CSAS). The meeting will generate a proceedings report summarizing the deliberations of the participants which will be published in the CSAS Proceedings Series. In addition, there will be a CSAS Research Document produced from the working papers presented and reviewed at the meeting and a Science Advisory Report which will document the resulting advice.

Participation

Participants will include DFO Science, DFO Fisheries and Aquaculture Management, Fisheries Joint Management Committee, Aklavik Hunter and Trappers Committee, and other members of the scientific community (e.g., university researchers).