Question Period Note: • Atlantic Mackerel Consumption by Predators

About

Reference number:
DFO-2024-QP-00002
Date received:
Dec 17, 2024
Organization:
Fisheries and Oceans Canada
Name of Minister:
Lebouthillier, Diane (Hon.)
Title of Minister:
Minister of Fisheries, Oceans and the Canadian Coast Guard

Suggested Response:

• The Fisheries Act requires rebuilding plans for all depleted fish stocks that are prescribed by regulation under the fish stocks provisions, such as Atlantic mackerel.
• Our Government is committed to accomplishing this work. That is why Budget 2024 announced $33 million over the next five years to support sustainable fisheries.
• Departmental and US scientists have investigated levels of predation on mackerel by various predators. Their results pointed to an overall increase in level of mackerel mortality from predation over time, with high year to year variability.
• Analysis of predation helps Fisheries and Oceans Canada to include ecosystem considerations into stock assessments and advice.
• At current low levels of mackerel abundance, predators are likely to take a larger share of the remaining stock.

Background:

BACKGROUND
• Atlantic Mackerel are a schooling pelagic fish that form dense aggregations and stick to a narrow temperature range (7-16°C). They are highly migratory, moving into the Gulf and then northward annually to spawn and feed. Accordingly, Atlantic Mackerel tend to move to Newfoundland waters later in the season relative to other parts of Atlantic Canada.
• Because of this high degree of local aggregations, mackerel are easy to harvest at very low levels and high overall population abundance cannot be inferred from high catches in localized areas.
• The commercial and bait fisheries were closed in 2022, while recreational and Food, Social, and Ceremonial (FSC) fisheries remained open. A limited personal use bait fishery of 470t will be open in 2024.
• The Canadian portion of the Atlantic Mackerel stock (predominantly NAFO subareas 3 and 4) is in the Critical Zone of the precautionary approach framework.
• The 2023 stock assessment showed that the spawning stock biomass (SSB) for mackerel declined to its lowest values in 2021 and 2022 (40 per cent and 42 per cent of the Limit Reference Point; LRP), relative to 79per cent and 56 per cent of the LRP in 2019 and 2020, respectively.
• The age structure remains truncated and this erosion has increased over time. There were very few fish over age 5 in 2021 and 2022 (3 per cent or less).
• The available evidence indicates the stock rebuilding potential is currently limited by a truncated age structure, low recruitment, and high predation pressure.
• In response to industry concerns about predation, DFO Science conducted an investigation of predation pressure on mackerel by various predators in Canadian and US waters for the 2023 assessment, which suggests an overall increase in predation-induced mackerel mortality over time. Prior to publication, the results of this work were presented to the Atlantic Mackerel Advisory Committee in February 2024. This study has now been published by the department and has gathered media interest.
• Compared to seals, Northern Gannets likely have a larger impact on predation induced mortality of mackerel (annual consumption by Northern gannets estimated to be between 11,000 – 23,000 over the last 10 years).

Additional Information:

If pressed on seal predation on mackerel
• Mackerel are a key prey source in the Northwest Atlantic ecosystem. Several predators are contributing to total natural mortality.
• They are an important prey species for Northern gannets and consumed by other seabirds, seals, groundfish, tunas and cetaceans. Mackerel is a minor prey source for grey seals, contributing only up to 4 per cent of their diet.
• Seal consumption of mackerel was found for example to be less than consumption by northern gannets.
• Given the current size of the grey seal population, the annual consumption of mackerel by grey seals was estimated to be between 7,000 and 13,000 t.

If pressed on the 2024 mackerel bait fishery
• On April 25th, I announced the opening of a 470 tonne (t) Atlantic mackerel personal-use bait fishery this spring, along with the continued closure of the Atlantic mackerel commercial fishery in Atlantic Canada and Quebec for the 2024 season.
• We understand the hardship the ongoing closure of the mackerel fishery is having on harvesters and the local communities they live in, and that purchasing mackerel for bait from other sources has become very expensive.
• We believe that this bait fishery will be beneficial for harvesters without jeopardizing the ongoing rebuilding of this stock.
• Fish caught under a bait licence are intended for personal-use and are not permitted to be sold, traded or bartered.