Terms of Reference

Review of a New Population Model for the Belcher Islands-Eastern Hudson Bay Beluga (Delphinapterus leucas) Stock

National Peer Review - National Capital Region

December 2-3, 2024

Montreal, QC

Chairpersons: Emma Hodgson and Lisa Setterington

Context

Beluga hunting is very important for Nunavik communities both from a cultural point of view and in terms of community food security. Nunavik hunters harvest belugas from at least four stocks that make up the Hudson Bay-Strait complex: Belcher Islands-Eastern Hudson Bay (BEL-EHB), Western Hudson Bay (WHB), Ungava Bay (UNG) and James Bay (JAM). The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has identified eight recognized designatable units (DUs) of beluga in Canada, including the Eastern Hudson Bay (Threatened) and the Ungava Bay (Endangered). A 5-year management plan (2021-2026) was developed with co-management partners to ensure sustainability of subsistence hunting across the Nunavik Marine Region.

An updated stock assessment of BEL-EHB beluga is necessary to ensure the sustainability of subsistence hunting and the conservation of this threatened stock. Without an updated assessment, Fisheries and Oceans Canada (DFO) cannot accurately assess the impact of subsistence harvests on population dynamics, and cannot recommend adjusted management measures and sustainable harvest levels. However, before the BEL-EHB beluga stock assessment can be updated, the new population model must first be reviewed.

The BEL-EHB beluga stock has so far been assessed using a stochastic, Bayesian stock-production model (Hammill et al. 2023). Over the last four decades, Nunavik harvesters have contributed to a beluga sampling program, which provides information on age, sex and genetic composition of harvested whales. In addition, recent research has demonstrated that progesterone levels from subcutaneous blubber can be used to estimate the reproductive status of beluga females (Renaud et al. 2023). Samples from this stock can provide valuable information on the demographic structure and life-history of BEL-EHB beluga, but this time series information is currently underused in the stock’s population model. Accordingly, and similarly to recent developments of population models used for grey seals, Northwest Atlantic harp seals and St. Lawrence beluga, a new integrated population model has been developed for BEL-EHB beluga. In addition to optimizing the use of available information from sampled belugas and increasing the consistency of the methods used to model marine mammal stocks nationally, this new model integrates environmental stochasticity as a factor influencing population dynamics, which addresses a request by co-management partners.

This project will support the ongoing Species at Risk Act regulatory process on Nunavik beluga, and is part of reconciliation efforts through a collaboration that values sampling efforts by Inuit communities and in the context of the implementation of treaties with Indigenous peoples.

Objectives

The specific objective of this meeting is to provide a scientific peer review of a new integrated population model for BEL-EHB beluga.

Expected Publications

• Research Document

Expected Participation

• Fisheries and Oceans Canada (DFO) (Ecosystems and Oceans Science, Fisheries Management)
• Environment and Climate Change Canada
• Makivvik, NMRWB, Nunavut Tunngavit Inc.
• Academia
• Other invited experts

References

• Hammill, M.O., St-Pierre, A.P., Mosnier, A., Parent, G.J., and Gosselin, J.-F. 2023. Total Abundance and Harvest Impacts on Eastern Hudson Bay and James Bay Beluga 2015–2022. DFO Can. Sci. Advis. Sec. Res. Doc. 2023/066. iv + 50 p.
• Renaud, L.-A., Bordeleau, X., Kellar, N.M., Pigeon, G., Michaud, R., Morin, Y., Lair, S., Therien, A., and Lesage, V. 2023. Estimating pregnancy rate from blubber progesterone levels of a blindly biopsied beluga population poses methodological, analytical and statistical challenges. Conserv Physiol 11(1): coad075; doi:10.1093/conphys/coad075.