Terms of Reference

Assessment Framework for Atlantic Herring (Clupea harengus) Stocks on the West Coast of Newfoundland and the Lower North Shore of Quebec (NAFO Divisions 4RSw): Part 1 - Review of Available Data for Modeling

Regional Peer Review - Quebec Region

April 4-5, 2023
Mont-Joli, Quebec

Chairperson: Jean-Martin Chamberland

Context

Atlantic herring (Clupea harengus) populations on the west coast of Newfoundland and the Lower North Shore of Quebec (NAFO Divisions 4RSw) are characterized by two spawning components. Spring spawners generally spawn in April and May, and fall herring, in August and September. Spring and fall spawning herring are considered separate stocks and are assessed separately. A first series of acoustic surveys was carried out in the fall between 1991 and 2002. A second series of surveys was initiated in the fall of 2009 and continued until 2021. These surveys target aggregations of both spring and fall spawners as they congregate near shore to feed, before beginning their migration to their wintering grounds. A summer acoustic survey was also initiated in 2019 to target fall spawner aggregations during their spawning season. The data collected from these surveys are used to calculate biomass indices and age composition for the two spawning stocks. The 2016 and 2018 assessments used a sequential population analysis (SPA) model to determine the status of the herring stocks on the west coast of Newfoundland (DFO 2016, 2018). The model used commercial fishery data and was calibrated with acoustic abundance indices. In 2020, concerns about certain aspects of the fall acoustic survey, particularly with respect to changes in catchability, led to the rejection of the SPA model as the basis for scientific advice, which resulted in the rejection of reference points and the precautionary approach (DFO 2021). During the 2020 assessment, it was determined that the review of the assessment framework was a priority. This meeting is the first of two and will be used to review the available data in order to establish a new assessment model and propose a new sampling and estimation methodology for the acoustic survey abundance index.

Objectives

The objectives of this first part are:

• Present the results of the first year of the acoustic telemetry study on herring in the northern Gulf of St. Lawrence and discuss the implications for the definition of biological and fisheries management units.
• To examine the available data and methods for calculating inputs, which would be used in the West Coast of Newfoundland herring stocks assessment model, including:
  • Catches at age in the commercial fishery;
  • Biomass index and numbers at age of acoustic surveys from 2009 to 2021.
• To present a new methodology for biological sampling and biomass estimation of the acoustic survey.

Expected Publications

• Research Documents
• Proceedings

Expected Participation

• Fisheries and Oceans Canada (DFO): Ecosystems and Oceans Science, and Fisheries Management
• Fishing Industry
• Provincial representatives
• Academia
• Indigenous Communities / Organizations
• Environmental Non-governmental Organizations

References

• DFO. 2016. Assessment of the West Coast of Newfoundland (Division 4R) herring stocks in 2015. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2016/024.
• DFO. 2018. Assessment of the West Coast of Newfoundland (Division 4R) herring stocks in 2017. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2018/036.
• DFO. 2021. Assessment of the West Coast of Newfoundland (NAFO Division 4R) Herring Stock in 2019. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2021/005.