Terms of Reference

National Marine Mammal Peer Review Committee (NMMPRC): November 2020 Biannual Meeting

National Peer Review - National Capital Region

November 16-20, 2020
Virtual meeting

Chairperson: Garry Stenson and Véronique Lesage

Context

The National Marine Mammal Peer Review Committee (NMMPRC) holds at least one annual meeting to conduct scientific peer-review of marine mammal research. Meetings provide the opportunity for collaborative review of scientific results by marine mammal experts from Fisheries and Oceans Canada (DFO) and with participation from other (non-DFO) organizations. Following NMMPRC peer-review and approval, scientific results are used to provide sound scientific advice for the management and conservation of marine mammals in Canada.

Topics

Specific Terms of Reference for each topic are as follows:

1. Pacific Region International Survey of Marine Megafauna (PRISMM)

Context

Several marine mammal species on the west coast of Canada are reported as by-catch in fisheries and aquaculture. A provision of the US Marine Mammal Protection Act (MMPA) will require Canada, as an exporter of fish products, to provide population estimates and rates of incidental mortality from fisheries operations by January 1, 2022. However, abundance estimates in Canadian Pacific waters are lacking for most cetacean species, especially for the offshore areas, or are too old to meet MMPA requirements. These species are not covered by current census programs and therefore must be assessed using a dedicated survey. Systematic surveys with the specific goal of estimating abundance of marine mammal species over the entire range of Canadian jurisdiction have been made in Atlantic Canada in 2007 and 2016 and in the Central Arctic in 2013, but never in Canadian Pacific waters.

To meet the US MMPA requirements, DFO Science completed a large-scale marine megafauna survey of Canadian Pacific (inshore and offshore) waters in July-August 2018. The results of the visual sightings during this survey and abundance estimates for some species) were presented to the NMMPRC in February 2020. However, it was not possible to estimate abundance of sperm whales from the visual sightings data.

A towed acoustic array was used to complement visual observation and offer 24-hour per day coverage, thus maximizing the use of available ship time, even at night and in mediocre weather conditions. This array can provide additional detections of rare and long/deep-diving species that are not readily observed using traditional methods, such as sperm and beaked whales, and can help identify small cetacean species. In addition, for species that have been detected both visually and acoustically in sufficient numbers (e.g., Dall’s porpoises and sperm whales), these data can be used as a double-platform experiment to calculate correction factors for animals missed by either survey method.

Objectives

• For Dall’s porpoise, to calculate an acoustic-based correction factor and abundance estimate, which will be compared to the abundance estimate calculated in February 2020 which was based on visual-only sightings. We will also evaluate whether it is possible to combine visual and acoustic-based abundance estimates to obtain a fully corrected estimate based on both sources of data.
• For sperm whales, an insufficient number of visual detections were made during the survey to calculate an abundance estimate in February 2020. Therefore, we will provide a correction factor, abundance estimate, and distribution based only on acoustic detections.

Expected Publications

• Research Document
• Science Advisory Report

2. Northern Hudson Bay Narwhal - Sustainable Harvest Advice

Context

Narwhal are listed on Appendix II of the Convention on International Trade in Endangered Species (CITES). CITES requires updated science and a documented management approach to show sustainable narwhal management. A non-detriment finding (NDF) from a DFO Scientific Authority is required to export narwhal products internationally. The Nunavut Agreement also requires a valid conservation basis on which to limit Inuit harvest. A Nunavut Wildlife Management Board (NWMB) decision will be required if a change in the current level of Total Allowable Harvest (TAH) is recommended. Hunters will be affected if they have to reduce their harvest in accordance to the TAH. Therefore Fisheries Management is requesting DFO Science provide a table of probabilities that the stock will decline in 10 years under a range of harvest scenarios (from 0-100% probability of decline)  for presentation to Inuit co-management organizations for a future NWMB decision.

Inuit subsistence harvests of Northern Hudson Bay (NHB) narwhal (Monodon monoceros) occur mainly in the Kivalliq Region of Nunavut, with smaller subsistence harvests in four Qikiqtaaluk Region communities (Sanirajak, Igloolik, Cape Dorset and Iqaluit) and in Inuit communities along Hudson Strait within the Nunavik Marine Region (Nunavik, Northern Quebec).

The NWMB established a TAH for NHB narwhal in 2012, informed by DFO aerial surveys conducted in 2011 (DFO 2012). The TAH, adjusted to account for hunting loss, was presented as a Total Allowable Landed Catch (TALC) of 157 NHB narwhals. Ten (10) NHB narwhal are allocated to Inuit of Nunavik and the balance, allocated among Nunavut communities by the Regional Wildlife Organizations (RWO). An aerial survey in 2018 estimated 19,200 (95% CI = 11,300–32,900) narwhal in the NHB narwhal population. With the addition of this abundance estimate, a model-based approach will be reviewed and advice regarding whether sustainable harvest advice can be generated from the model for future requests for NWMB decision.

Objectives

• To determine whether a model-based approach is suitable for providing sustainable harvest advice for the NHB narwhal population, and if so, should the model-based approach take priority over the Potential Biological Removal (PBR) threshold determined from the 2018 aerial survey estimate for NHB narwhal. 
• To provide information on the probability that the stock will decline in 10 years under a range of harvest scenarios (from 0-100% probability of decline).

Expected Publications

• Research Document
• Science Advisory Report

3. Genetic identification of Eastern Hudson Bay beluga stocks

Context

In 2004, COSEWIC designated the Eastern Hudson Bay (EHB) beluga population as Endangered.  A three-year subsistence harvest management plan was established by the Nunavik Marine Region Wildlife Board in 2014, and renewed in 2017; this plan expired in 2020, at which time an interim plan was put in place to ensure that subsistence harvesting of beluga by Nunavik Inuit is managed under a Total Allowable Catch (TAC) regime which takes into account the relative proportion of this stock in the regional hunt. As populations cannot be discriminated visually, this proportion is estimated using genetic analyses of skin samples obtained from hunters.

The latest genetic analyses classified catches from the Nunavik as either from EHB or Western Hudson Bay (WHB) populations. Genetic characteristics of these reference populations were identified using a short or a long version of a sequence of mitochondrial DNA (mtDNA) and samples from July and August from 1982 to 2015. A genetic mixture analysis using the Statistics Program for Analyzing Mixtures was then realized to estimate the proportion of Nunavik catches attributed to one of the two reference populations.

With the recent advances in genetic research, development of specialized software and additional sampling, it is possible to re-examine the capacity of the longer mtDNA sequences to identify more reference populations to improve the classification of catches to reference populations in the eastern Arctic area. The improved approach will also provide uncertainty estimates for the classification to the reference population of annual catches from Nunavik. Samples acquired in 2019 will be used for comparative purposes between previous and new approaches of classification.

Objectives

To define biological units using a genetic marker and novel statistical approaches, and to compare two genetic mixture analyses to estimate proportions of reference populations from hunting specimens.

Expected Publications

• Research Document
• Science Advisory Report

Expected Participation

• DFO (Ecosystems and Oceans Science, Species at Risk, Fisheries and Harbour Management sectors)
• Academia or Academics
• Stakeholders
• Other invited experts