Terms of Reference

Science Advice on Habitat-based Reference Points for Saint John River Alewife, Upstream of Mactaquac Dam

Regional Peer Review - Maritimes Region

January 12-13, 2023
Darthmouth, NS

Chairperson: Darek Moreau

Context

The status of Alewife (Alosa pseudoharengus) in the Saint John River upstream of Mactaquac was last assessed in 2001 (Jessop 2001). Monitoring of fish trucked over the Mactaquac dam has continued since then. Escapement targets of 800,000 Alewife and 200,000 Blueback Herring have been in place since 1995, based on negotiations with stakeholders and the assumption that the spawning habitat was limited to the Mactaquac headpond. After the 2019 spawning run, it was decided that commercial harvesting would cease at Mactaquac dam, and escapement targets would increase from 800,000 Alewife and 200,000 Blueback Herring to as many fish as possible. Reference points for Alewife are required to inform the status of the stock, to inform escapement targets, and to inform decisions on fishing effort. Reference points for Blueback Herring are also required; however, the meta-analysis of carrying capacity is not available for Blueback Herring to calculate reference points. Reference points for this Alewife stock subunit will be developed following the procedure described by Gibson et al. (2017) for implementing proxy reference points based on the available spawning habitat and the median habitat carrying capacity when suitable spawner recruit data are not available.

Objectives

The specific objectives for this process are:

• To provide an estimate of the spawning habitat for Alewife above Mactaquac Dam and below Grand Falls;
• To provide an estimate of the abundance and reference points for Alewife that this area could theoretically support; and
• To provide an estimate of the carry capacity and reference points for Alewife that this area currently supports based on fish passage.

Expected Publications

• Science Advisory Report

Expected Participation

• Fisheries and Oceans Canada (DFO) Resource Management
• Fisheries and Oceans Canada (DFO) Science
• Provincial government
• Academia
• Indigenous communities/organizations
• Non-government organizations

References

• Gibson, A.J.F., Bowlby, H.D., and Keyser, F.M. 2017. A Framework for the Assessment of the Status of River Herring Populations and Fisheries in DFO’s Maritimes Region. DFO Can. Sci. Advis. Sec. Res. Doc. 2016/105. vi + 69 p.
• Jessop, B.M. 2001. Stock status of alewives and blueback herring returning to the Mactaquac Dam, Saint John River, N.B. DFO Can. Sci. Advis. Sec. Res. Doc. 2001/059. 27 p.