Terms of Reference

Stock Assessment for Lake Whitefish (Coregonus clupeaformis) and Lake Trout (Salvelinus namaychus) in Great Slave Lake, Northwest Territories, 2022

Regional Peer Review - Ontario and Prairie Region

May 22-24, 2024

Winnipeg, MB

Chairperson: Joclyn Paulic

Context

The fisheries of Great Slave Lake (GSL) are dominated by three species, Lake Whitefish (Coregonus clupeaformis), Lake Trout (Salvelinus namaychus) and Inconnu (Stenodus leucichthys). The development of an Integrated Fisheries Management Plan (IFMP) is critical for the long-term management of lake fisheries. There are ongoing pressures on DFO Science to provide robust advice on the stock status for Great Slave Lake fisheries to support the establishment of sustainable harvest levels and limit reference points for each of the three dominant species. A previous assessment of Lake Whitefish for GSL was not definitive due to missing data at the time of the assessment (DFO 2015). Lake Trout has not been assessed in recent decades.

DFO Fisheries Management has requested that DFO Science provide advice on the stock status, abundance and sustainable harvest levels for the key commercial fishery species, Lake Whitefish and Lake Trout. Since it has been some time since the first assessments in GSL, a framework review was conducted in May 2023 to explore the available data and modeling approaches for each stock with the aim of selecting the highest level possible in quantitative analysis. The recommendations from this meeting provide the direction for quantitative analysis (i.e., models) in this stock assessment.

Objectives

The objectives of this peer-review meeting are to provide Science advice on sustainable harvest levels for Lake Whitefish (Coregonus clupeaformis) and Lake Trout (Salvelinus namaychus) in Great Slave Lake. To achieve this objective, we aim to:

1. summarize and review best available data (including but not limited to fisheries-dependent and/or fishery-independent data) to assess trends in harvest, catch effort, and biological indicators;
2. incorporate these data into population models to estimate time-series for stock status, and estimate the population abundance/biomass, sustainable harvest levels, and identify associated uncertainties (e.g., climate change);
3. evaluate candidate reference points (Limit and Upper Stock Reference) consistent with DFO’s Precautionary Approach framework using an appropriate spatial scale (e.g., lake-wide, management area(s), river system, genetic unit); and,
4. initiate the discussion for future research to include environmental and climate change considerations, and other anthropogenic impacts affecting stock(s).

Expected Publications

• Science Advisory Report
• Research Document

Expected Participation

• Fisheries and Oceans Canada (DFO) (Science and Fisheries Management sectors)
• Government of Northwest Territories
• Tlicho Government
• Province of Manitoba
• Local Community Members
• Other invited experts

References

• DFO. 2015. Assessment of Lake Whitefish Status in Great Slave Lake, Northwest Territories, Canada, 1972–2004. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2015/042.