Rebuilding plan - Atlantic mackerel (Scomber scombrus L.): Northwest Atlantic Fisheries Organization sub-areas 3 and 4

• Date stock was determined to be at or below the limit reference point: 2011
• Date stock was prescribed to the Fish Stocks provisions: April 4, 2022
• Date rebuilding plan was approved: April 12, 2024

Foreword

In 2009, Fisheries and Oceans Canada (DFO) developed A Fisheries Decision-Making Framework Incorporating the Precautionary Approach (PA Policy) under the auspices of the Sustainable Fisheries Framework. It outlines the departmental methodology for applying the precautionary approach (PA) to Canadian fisheries. A key component of the PA Policy requires that when a stock has declined to or below its limit reference point (LRP), a rebuilding plan must be in place with the aim of having a high probability of the stock growing above the LRP within a reasonable timeframe.

In addition, under section 6.2 of the Fish Stocks provisions (FSP) in the amended Fisheries Act (2019), rebuilding plans must be developed and implemented for prescribed major fish stocks that have declined to or below their LRP. This legislated requirement is supported by section 70 of the Fishery (General) Regulations (FGR), which set out the required contents of those rebuilding plans and establish a timeline for each rebuilding plan’s development.

The purpose of this plan is to identify the main rebuilding objectives for Atlantic mackerel in Northwest Atlantic Fisheries Organization (NAFO) subareas 2 to 5 as well as the management measures that will be used to achieve these objectives. This plan provides a common understanding of the basic “rules” for rebuilding the stock. This stock is prescribed in the Fishery (General) Regulations (section 69) and thus is subject to section 6.2 of the Fisheries Act and regulatory requirements.

The objectives and measures outlined in this plan are applicable until the stock has reached its rebuilding target. Once the stock is determined to be at the target, the stock will be managed through the standard Integrated Fisheries Management Plan (IFMP) or other fishery management process in order to fulfill the requirements of the FSP. Management measures outlined in this rebuilding plan are mandatory, and may be modified or further measures added if they fail to result in stock rebuilding.

Decisions flowing from the application of this rebuilding plan must respect the rights of Indigenous peoples of Canada recognized and affirmed by section 35 of the Constitution Act (1982), including those through modern treaties. Where DFO is responsible for implementing a rebuilding plan in an area subject to a modern treaty, the rebuilding plan will be implemented in a manner consistent with that agreement. The plan should also be guided by the 1990 Sparrow decision of the Supreme Court of Canada, which found that where an Aboriginal group has a right to fish for food, social and ceremonial purposes, it takes priority, after conservation, over other uses of the resource.

On this page

• 1.0 Introduction and context
  • 1.1 Population and distribution
  • 1.2 Biology
  • 1.3 Ecosystem interactions
    • 1.3.1 Ecosystem effects on the stock
    • 1.3.2 Fishery effects on the ecosystem
  • 1.4 The fishery
  • 1.5 The socio-economic and cultural importance of Atlantic mackerel
    • 1.5.1 The commercial fishery
    • 1.5.2 Indigenous fishery
    • 1.5.3 Recreational fishery
    • 1.5.4 Trade profile
    • 1.5.5 U.S. fishery
• 2.0 Stock status and stock trends
  • 2.1 Committee on the Status of Wildlife in Canada (COSEWIC)
  • 2.2 Indigenous Knowledge
• 3.0 Probable causes for the stock’s decline
• 4.0 Measurable objectives aimed at rebuilding the stock
  • 4.1 Rebuilding target and timeline
  • 4.2 Additional measurable objectives and timelines
• 5.0 Management measures aimed at achieving the objectives
• 6.0 Socio-economic analysis
• 7.0 Method to track progress towards achieving the objectives
• 8.0 Periodic review of the rebuilding plan
• References
• Annex A – Income dependency analysis

1.0 Introduction and context

1.1 Population and distribution

Atlantic mackerel (Scomber scombrus L.) is a widely distributed transboundary small pelagic marine fish species found in both the Northeast Atlantic Ocean (Europe) and the Northwest Atlantic Ocean (North America). The Northwest Atlantic population is composed of two spawning groups: the southern (United States [U.S.]) contingent that spawns both offshore of southern New England and in the western Gulf of Maine in April-May, and the northern (Canadian) contingent that spawns mostly in the southern Gulf of St. Lawrence in June and July. After spawning, northern contingent mackerel (henceforth Atlantic mackerel) undertake an extensive feeding migration throughout Atlantic Canada and Quebec waters from July to October, after which they migrate south to Sable Island and into U.S. waters to mix with the southern contingent during late fall and winter.

1.2 Biology

Atlantic mackerel spawning occurs in near surface waters of 8°C or warmer. Eggs hatch after a few days and larvae grow while consuming plankton for about 3 weeks before metamorphosing into juveniles, which can reach a length of 20 cm by November of the first year of growth. Recruitment is dependent on favourable water temperatures and the availability of suitable prey. Atlantic mackerel typically mature by age 2 or 3 and can live for over 15 years and reach a maximum size of 45 cm. The presence of older spawning adults in the population is desirable as they contribute a greater amount of higher quality eggs compared to smaller younger spawning adults.

Atlantic mackerel, like other forage fish stocks, display large variations in recruitment and spatial distribution. Changes in Atlantic mackerel distribution, recruitment, survival, and growth are known to vary with changes in temperature and the availability of prey among other factors.

1.3 Ecosystem interactions

1.3.1 Ecosystem effects on the stock

This section summarizes available knowledge on how ecosystem factors affect three fundamental productivity processes (recruitment, natural mortality, and growth), which determine the rate at which the Atlantic mackerel stock will rebuild, and how this knowledge was integrated within the assessment.

The drivers of Atlantic mackerel recruitment variability have been analyzed several times. The latest and most in-depth study demonstrated that Atlantic mackerel recruitment is determined by larval food conditions; stock state (i.e., spawning stock biomass [SSB] and maternal body condition); the intensity of the spatial and temporal match between specific larval prey; and, egg production is correlated to recruitment strength (match-mismatch hypothesis^{Footnote 1}). Since projections are currently performed over a three-year period and the first projected year has the largest impact on the final year projected, the demonstrated fine-scale nature of the recruitment process makes long-term ecosystem-informed projections extremely difficult. The uncertainty in future recruitment projections is caused by directional trends of known environmental drivers. This is accounted for in the stock assessment report by projecting multiple scenarios under different statistical assumptions.

Natural mortality caused by a range of predators can be substantial, especially when SSB is low. The main predators identified by the most recent stock assessment were northern gannets, Atlantic bluefin tuna, grey seals, cetaceans, and U.S. groundfish. Available evidence does not indicate that natural mortality had a key role in causing the stock decline (i.e., no corresponding increase in Atlantic mackerel consumption by the indicated predators). Once SSB reached lower levels, predators are however likely to remove a relatively larger proportion of the stock, and an increase in natural mortality will affect stock rebuilding. This is especially true as the consumption of Atlantic mackerel by gannets, tuna and seals is likely to have gradually increased with the rise in predator population abundance. Although an effort was made to estimate the minimal biomass removed by predators for the 2023 assessment, this information remains uncertain and this uncertainty, compounded with technical challenges, currently prevents its explicit incorporation into the assessment model, which assumes a constant natural mortality rate. Nonetheless, this estimate will continue to be pursued as information becomes available.

The ecosystem factors affecting Atlantic mackerel growth have not yet been specifically investigated. However, between-year changes and within-year gains in body condition show correlation with plankton abundance. Atlantic mackerel weight-at-age, used as an assessment input, also does not display prominent patterns over time, and small-amplitude variations caused by changing environmental conditions do not significantly affect the assessment. Although ecosystem components associated with Atlantic mackerel growth are currently unaccounted-for, they are considered to be of minor importance in determining stock productivity relative to recruitment and natural mortality.

Although environmental conditions drive the annual Atlantic mackerel migration pattern^{Footnote 2}, there is currently no evidence that changes in spatial distribution have a direct impact on stock productivity and thus rebuilding.

1.3.2 Fishery effects on the ecosystem

Atlantic mackerel is a forage fish species at the middle of the food web. They play a key role in the ecosystem through the transfer of energy from lower trophic levels to higher-order predators. The effect of fishery-induced changes in mackerel stock state on most predators is unknown, with the exception of northern gannets. This seabird species is the only predator known to feed predominantly on mackerel when they are available, but the decline in breeding success of northern gannets in the southern Gulf has been associated with the decrease in Atlantic mackerel SSB.

Bycatch of other species in the Atlantic mackerel fishery is relatively small and not known to significantly affect these stocks.

1.4 The fishery

The Canadian Atlantic mackerel fisheries are managed predominantly in Northwest Atlantic Fisheries Organization (NAFO) sub-areas 3 and 4 (Figure 1); however, this forage species has supported commercial, bait, recreational, and Indigenous food, social and ceremonial (FSC) fisheries in the five eastern Canadian provinces (NAFO sub-areas 2 to 5) in spring, summer, and fall. Both the northern and southern contingents mix in winter in deeper warmer waters, on the edge of the continental shelf from Sable Island, Nova Scotia, to the waters off Cape Lookout, North Carolina in the U.S. (NAFO sub-areas 5 and 6). During this time, they are targeted by the U.S. fishing fleet.

There is indication of small but significant genetic differentiation between the northern and southern contingents; however, the level of mixing during winter remains highly uncertain and variable year to year but is likely significant overall. To assess and manage the stock, it is necessary to account for all removals of northern contingent fish, historically and in the future. An assumption applied in the latest Canadian assessment is the proportion of northern contingent fish (Canadian) in U.S. landings, which ranged from 20-80 percent, in accordance with the most recent knowledge on stock mixing.

The commercial mackerel fishery in North America dates back to the 1600s but landings were only regularly recorded as of the early 1800s. Atlantic mackerel was primarily a food fishery throughout the 1800s and was originally fished with beach seines, nets, and handlines. The fishery grew rapidly after the development of improved salting techniques in the 1820s. Catches increased after the purse seine fishing gear was developed in the early 1850s and came to dominate the fishery by the 1870s. From 1803-1900, the average combined Canadian and U.S. catches were around 34,500 metric tons (mt) annually, reaching a high of around 106,000 mt in 1884. Total catches declined substantially near the end of the 19th century as American vessels were gradually denied access to Canadian fishing grounds. In the 1920s, catches in both Canada and the U.S. increased due to power-driven mobile gear harvesting.

Offshore foreign fleets, primarily from European and Asian countries, fished in waters off North America from 1961 until 1978, in NAFO Division 3Ps and sub-areas 4, 5, and 6. Between 1970 and 1976, total catches of mackerel were upward of 240,000 mt, reaching a maximum of nearly 420,000 mt in 1973. Following the imposition of the 200 nautical mile exclusive economic zones by the U.S. and Canada, total catches dropped as the foreign fleets no longer had access to Atlantic mackerel within those areas. However, catches by foreign fleets persisted in Canadian waters until 2004 as allocations were given to foreign vessels. France (St. Pierre & Miquelon) remains the only fleet other than Canada’s that still captures Atlantic mackerel in sub-areas 3 and 4. These landings are very low and mainly landed as bycatch in other fisheries.

During the 1980s and 1990s, landings by Canadian vessels were relatively stable and averaged around 22,000 mt per year. Canadian landings reached a record high of 55,726 mt in 2005 due to the marked increase in fishing effort by small and large seiners on the east and west coasts of Newfoundland (NAFO divisions 3KL and 4R) and the presence of an exceptional 1999 year class. From 2000 to 2010, landings averaged 40,498 mt. This was followed by a large drop in landings, reaching a low of 4,272 mt in 2015. This decline was accompanied by poor recruitment over several years, and the loss of Atlantic mackerel over 7 years old from the population. Nominal landings from 2017-2021 were 9,679 mt, 10,905 mt, 8,628 mt, 7,835 mt, and 4,326 mt, respectively. The total allowable catches (TAC) were 10,000 mt from 2017-2018 and 8,000 mt from 2019-2020. In 2021, the TAC was 4,000 mt, which represented a 50 percent reduction from 2020. In 2022 and 2023, the commercial and bait fisheries were closed in response to the depleted status of the stock and conservation concerns.

In DFO Maritimes, Gulf, Quebec, and Newfoundland and Labrador regions (NAFO sub-areas 2, 3, 4, and part of 5), several hundred commercial fishers participated in the Atlantic mackerel fishery on a competitive basis. They fished mainly inshore using gillnets, jiggers, handlines, seines, traps, and weirs, depending on the region and the time of year. The majority of landings occurred between June and October.

The three provinces with the largest landings prior to the 1990s were Nova Scotia, Prince Edward Island, and Quebec. After 1990, the landings in the Gulf of St. Lawrence and Nova Scotia dominated the fishery. Since 2000, however, landings by fish harvesters in Newfoundland and Labrador have exceeded those of other provinces by a large margin. In fact, annual landings in that province exceeded 40,000 mt three times between 2004 and 2010, representing 80 percent of total Canadian landings during that period.

Prior to the early 2000s, gillnets, jiggers, and traps accounted for the majority of Canadian mackerel catches. The majority of catches since the mid-2000s have been by the small (<19.8 m) and large (>19.8 m) seiners, which were used primarily in Newfoundland and Labrador. Between 2002 and 2007, small seine landings ranged from 10,833 mt to 29,161 mt, and large seine landings from 6,074 mt to 14,645 mt. In more recent years, small seiners (purse, tuck, and bar) have landed the majority of the catch in the commercial fishery.

Fishing for bait is authorized by licence through DFO’s National Online Licensing System in all regions. Harvests under the bait licence are for personal use by the harvester and are not permitted to be sold, traded, or given away. This bait fishery provides multi-licensed harvesters the opportunity to catch their own baitfish, which is used for fisheries such as tuna, lobster, and crab. In 2021, bait landings were approximately 536 mt. However, unreported landings in the mackerel bait fishery and the recreational fishery have been a longstanding issue.

Recreational fishing for Atlantic mackerel is practiced throughout Eastern Canada and does not require a licence. Historically, there were no possession limits in this fishery or close times, allowing fishers to catch unlimited amounts of Atlantic mackerel. Past DFO observations indicate that it was not uncommon for vessels engaging in recreational fishing to land over 500 kg of Atlantic mackerel per day, which could have been used to avoid monitoring obligations in the commercial and bait fisheries and would also undermine data collection efforts. Regulatory amendments to the Atlantic Fishery Regulations, 1985, came into effect in May 2021 and instituted limits on the recreational fishery. These amendments established a yearly close time from January 1 to March 31, set a daily possession limit (20 fish) for recreational purposes, limited gear to 5 fishing lines with a maximum of 6 hooks per line, and set a new minimum size (26.8 cm). Better control and knowledge of catches will support rebuilding of the stock.

Atlantic mackerel are culturally significant to Indigenous communities in Atlantic Canada. There are Indigenous communities that hold commercial communal fishing licences for Atlantic mackerel. There are also FSC Agreements between Indigenous groups and DFO that include access to Atlantic mackerel for FSC purposes. For privacy reasons, information regarding FSC annual landings is withheld due to participation by only a small number of Indigenous groups throughout the years. However, all landed weights and values for Indigenous commercial communal fisheries are included in the total Canadian reported landings.

In the Atlantic provinces and Quebec (NAFO sub-areas 2 to 4), DFO issued approximately 7,757 total commercial licences with 499 active licences, and 7,054 bait licences (i.e., for personal-use) with 383 active licences for the Atlantic mackerel fishery in 2021 (Table 1). Harvesters fish mainly inshore using gillnets, automatic jiggers (mechanical device), handlines, tuck seines, purse seines and traps. The type of gear used varies according to the region and time of the year.

Table 1: The number of commercial licences by gear type and bait licences in 2021 for the Atlantic Regions and Quebec. Included in the number of commercial licences are communal commercial mackerel licences issued to Indigenous organizations.

Notes:

1. ^A Regional bait licences may include multiple species (e.g., Atlantic herring, Atlantic mackerel, winter flounder).
2. ^B In Quebec, 14 licence holders also have access to Mackerel Fishing Area 14

1.5 The socio-economic and cultural importance of Atlantic mackerel

1.5.1 The commercial fishery

The value of Atlantic mackerel landings by Canadian harvesters remained relatively stable in the 1990s but increased substantially in the 2000s. Values reached a record high of $25.3 million (M) in 2005, with the expansion of the fishery in Newfoundland and Labrador. More recently, between 2017 to 2021, the total annual landed value for Atlantic mackerel averaged $9.7M, with a value of $8.6M in 2021, which was 0.2 per cent of Canada’s total landed value that year. In the same period, Prince Edward Island had the largest share of landed value at 35 per cent, followed by Nova Scotia (25 per cent), Newfoundland and Labrador (22 per cent), Quebec (12 per cent), and New Brunswick (6 per cent). Of the 753 fishing enterprises that landed Atlantic mackerel in Canada in 2021, 582 of enterprises (77 per cent) fished for lobster as their main species^{Footnote 3},^{Footnote 4}. On March 30, 2022, Atlantic mackerel directed commercial and bait fisheries were closed in support of stock rebuilding. As a result, only a minimal amount (74 mt) of mackerel landings were reported in 2022^{Footnote 5}, which was mainly bycatch from the herring fisheries and some groundfish fisheries.

Figure 2 shows a combined line and bar graph which plots the value and quantity, respectively, of Canada’s Atlantic mackerel landings from 2012 to 2022. Landings fluctuated during this period, with a declining trend in the early years of the reporting period, dropping to approximately 4,100 mt in 2015. This was followed by a rise in subsequent years, peaking at around 11,100 mt in 2018. The value of landings followed a similar trend, except for 2015, when prices were unusually high, offsetting impacts from lower landings. Since 2018, landings have seen a downward trend as a result of reductions in TAC – in response to science advice. The TAC was reduced by 20 per cent (relative to 2017 and 2018) to 8,000 mt in 2019 and further reduced by 50 per cent to 4,000 mt in 2021. Despite the 50 per cent reduction in TAC (or a 44 per cent reduction in actual landings) in 2021, the landed value was $8.6M, only five per cent below the 2020 level, due to strong prices.

In the 2021 Atlantic mackerel fishery, there were a total of 753 fishing enterprises in Atlantic Canada and Quebec that included mackerel as part of their harvest, a slight increase from 742 mackerel fishing enterprises in 2020. For these 753 mackerel fishing enterprises, total landings of all species amounted to 53,689 mt^{Footnote 6} with a total landed value of approximately $273.4M in 2021. Landed value for the main species is as follows: lobster at $195.2M (71 per cent^{Footnote 7}); snow crab at $27.6M (10 per cent); Atlantic halibut at $13.9M (5 per cent); Atlantic mackerel at $8.6M (3 per cent); and haddock at $7.3M (3 per cent).

The average dependency ratio on Atlantic mackerel for these 753 mackerel fishing enterprises was 14.8 per cent ^{Footnote 8} (i.e., on average, 14.8 per cent of total landed revenues were from mackerel landings). There were 89 fishing enterprises that harvested Atlantic mackerel as their main species (i.e., dependency > 50 per cent).

The average landed value for all species caught was $30,263, of which 91.3 per cent was from Atlantic mackerel. Of these, 52 enterprises reported Atlantic mackerel as their exclusive catch in 2021, with an average landed value of $6,757 per enterprise. Looking at the historical trend since 2010, the average value of Atlantic mackerel landings by enterprises relying exclusively on the species has remained within the historical range since 2010 (averaging $11,117 per enterprise annually). However, during the same period the number of enterprises with 100 per cent revenue dependency on mackerel increased from 22 in 2010 peaking to 52 in 2021.

At the regional level, in 2021, the Gulf Region featured the highest number of Atlantic mackerel fishing enterprises (404 enterprises, or 54 per cent of total mackerel fishing enterprises). The Maritimes Region had 251 enterprises (33 per cent), while 76 enterprises (10 per cent) were identified in Quebec, and 24 enterprises (3 per cent) in Newfoundland and Labrador ^{Footnote 9}. The average dependency of Atlantic mackerel was the highest in the Maritimes Region (20.9 per cent) followed by Quebec (20.1 per cent), Gulf (10.5 per cent) and Newfoundland and Labrador (5.1 per cent). The detailed dependency analysis for the Atlantic mackerel fishery can be found in Annex A.

It is estimated that approximately 2,300 crew members (including licence holders and hired harvesters) participated in the Atlantic mackerel fishery in 2021:

• 1,925 crew members (or 84 per cent) were associated with enterprises with a dependency on mackerel fishing that is lower than 25 per cent.
• 295 crew members (or 13 per cent) were associated with enterprises with a dependency on mackerel fishing that is greater than 50 per cent. Of these, 175 crew members (or 8 per cent) were associated with enterprises that exclusively caught Atlantic mackerel in 2021.

The overall dependency on mackerel is considered low for all mackerel fishing enterprises, given that an average of less than 15 per cent of the landed revenues was from Atlantic mackerel harvesting in 2021. A significant quantity of Atlantic mackerel harvested commercially has been sold as bait for other fisheries including lobster, crab, tuna, and halibut, which compounds the economic importance of mackerel. Lower domestic supplies of bait in recent years, due to the declines in the Atlantic herring stocks and the closure of the Atlantic mackerel commercial and bait fishery, has increased the need for bait imports. Bait prices have risen considerably in both domestic and international markets, which is likely to have resulted in a higher share of expenses allocated to bait purchase for the fishing enterprises that depend on Atlantic mackerel as bait, which may have a slight impact on profits.

After the closure in 2022, a number of affected harvesters advocated for a compensation program. Currently, there is no automatic compensation program to assist community members who are affected by a fishery closure, which DFO expects to be temporary. It should be recognized, however, that cultural and socio-economic factors are considered within the Fish Stocks provisions (FSP) under subsection 6.1(2) and, most pertinently in this case, 6.2(2) of the Fisheries Act, and financial assistance could provide an alternative means of mitigating these concerns while undertaking rebuilding.

1.5.2 Indigenous fishery

A number of Indigenous communities in Eastern Canada have access to Atlantic mackerel for FSC (Food, Social, and Ceremonial) purposes. For centuries, harvests and use of fish by Indigenous communities have had important food, social, and cultural significance and value. When Europeans first arrived in Canada, several Indigenous communities were already harvesting Atlantic mackerel. The reflection of some of these aspects (i.e., social and cultural significance) in economic metrics and concepts may not be compatible with the holistic perspective that is reflected in Indigenous cultural and social values attached to the species under consideration. Despite the closure of the commercial and bait fisheries in 2022, the FSC fishery has remained open for Atlantic mackerel.

On the commercial communal fishery side, between 2017 and 2021, on average, a total of 17 Indigenous communities held 190 licences for inshore Atlantic mackerel in the Gulf Region, nine communities in the Maritimes held 16 licences, nine communities in Quebec held 14 licences, and three communities in Newfoundland and Labrador held 18 licences.

1.5.3 Recreational fishery

The recreational fishery for Atlantic mackerel is practiced throughout Eastern Canada by many people, including tourists, at dockside or aboard charter vessels. Although Atlantic mackerel is not one of the top recreational species caught in Canada overall, DFO’s 2015 Recreational Fishing survey found it was one of the top three species caught recreationally in Prince Edward Island and Nova Scotia.

Recreational removals are estimated using the Survey of Recreational Fishing in Canada, 2015; however, there is an associated lack of current landing data as the Atlantic mackerel recreational fishery is not licensed, and landings remain unreported. Although a new estimate will be developed once the next recreational survey is conducted, the recreational fishery remains open as removals are not expected to significantly affect rebuilding.

1.5.4 Trade profile

The European Union (E.U.) and the United States (U.S.) have been the main export markets for Canadian mackerel^{Footnote 10},^{Footnote 11}. Historically, mackerel was primarily frozen whole for delivery to the domestic and export bait and food markets and did not typically undergo significant processing before shipment. In recent years up until the bait and commercial closures, Canada’s total exports of Atlantic mackerel had seen a general and notable trend downwards corresponding with a decline in the TAC (Figure 3), with a significant decline in the exports of frozen Atlantic mackerel while prepared or preserved exports remained steady. It should be noted that the Atlantic mackerel exports reported in 2022 may have included past landings stored in inventory or imported mackerel from abroad that has been subsequently exported, or re-exported, after processing. However, such detailed assumptions cannot be confirmed using available trade data.

Canada’s annual mackerel import value has increased every year since 2018 despite a slight decline in the quantity of imports in 2022 (Figure 4). In 2022, Canada’s mackerel imports were valued at $33.1M, representing less than 1 per cent of Canada’s total fish and seafood import value^{Footnote 12} . Since 2018, the E.U, Iceland, and the U.S. have been key sources of mackerel imports. Frozen mackerel accounts for the majority of total mackerel imports in recent years, followed by prepared and preserved mackerel, and fresh and chilled mackerel. It has been suggested that a portion of the mackerel imports is used as bait in the lobster and snow crab fisheries, but the actual amount is unknown as the trade data does not provide details on the end-use of imports.

Demand for bait used in the lobster and snow crab fisheries, combined with the declines in Atlantic herring stocks and the closure of the Atlantic mackerel commercial and bait fisheries, has increased the need for imports of bait in recent years. In recent years, the import of baitfish has grown significantly, totaling approximately 35,800 mt – which was valued at $80.1M in 2022 (Figure 5^{Footnote 13}) . While a portion of the mackerel imports is used as bait as discussed above, additional shipments of mackerel, along with other bait species, may have been imported specifically for bait use and have been categorized as baitfish in the trade data. However, the amount of mackerel being imported as baitfish is unavailable because species-specific information is not provided for the baitfish category in the trade data.

1.5.5 U.S. fishery

The U.S. Atlantic mackerel fishery is managed by the National Oceanic and Atmospheric Administration (NOAA) and is an important factor to consider with respect to the future sustainability of the stock, as annual U.S. removals of Canadian-spawned mackerel can be significant. Industry stakeholders and groups affected by the closure are concerned that Canada’s rebuilding plan could be undermined, since some Canadian-spawned mackerel could still be harvested by the U.S. when migrating south during the winter.

In 2021, the U.S. commercial Atlantic mackerel fishery landed a total of 5,474 mt which was valued at $3.1M (USD)^{Footnote 14}. Pending the availability of catch opportunities, the U.S. commercial fishery operates year-round, with harvesting occurring between January and May in southern New England and Mid-Atlantic coastal waters and focusing on the Gulf of Maine between May and December. Another notable difference in the U.S. and Canadian fisheries is that the U.S. has not established a minimum size. The U.S. TAC is set by determining an Allowable Biological Catch (ABC) and then subtracting U.S. recreational catch, commercial discards, and an estimation of Canada’s catch to determine the cumulative commercial quota for the upcoming season.

In 2022, the year when the Canadian directed commercial and bait fisheries first closed, the U.S. reduced its Atlantic mackerel commercial quota from 17,312 mt to 4,963 mt due to conservation concerns^{Footnote 15}. The U.S. reduced its commercial quota again in 2023 to 3,639 mt, while also assuming a lower Canadian commercial catch (from 4,200 mt to 2,197 t). This reduction of Canada’s estimated Atlantic mackerel catch can be interpreted as the U.S. reallocating some of Canada’s foregone catch to their own commercial quota.

The Mid-Atlantic Fisheries Management Council (MAFMC), which provides advice to the U.S. government, once again decreased Canada’s annual catch estimate to 74 mt in its advice for the 2024 and 2025 fishing seasons. This advice was approved by the National Marine Fisheries Services (NMFS) and also included a 76 per cent decrease to the U.S. commercial quota to 868 mt, while maintaining recreational removal levels at the 2023 amount (i.e., 2,143 mt)^{Footnote 16}.

The significant reduction in the U.S. ABC is promising considering the reduced harvest this entails. However, concerns remain as Canadian fishing effort is displaced and taken up by American harvesters. This does undermine the actions that Canada has taken to protect the stock to some extent. Although this transboundary stock is managed by Canada and the U.S. independently, it should be noted that both countries have made strong commitments to rebuilding the Atlantic mackerel population to help ensure the future sustainability of the stock.

With the involvement of Canadian scientists, the most recent U.S. mackerel management track assessment, published in July 2023, analyzed data from both northern and southern contingents. The data suggests the population is no longer under the influence of overfishing (i.e., F<F_msy), but is still in an overfished state (i.e., B<B_msy) requiring rebuilding which, in the U.S. context, means building the stock to B_msy. The U.S. stock assessment also updated the fishing mortality rate for rebuilding to 0.11 because it would yield a 61.5 per cent probability of rebuilding the stock by 2032. After the results of this assessment were published, MAFMC requested a sensitivity analysis to examine the influence of recruitment on the expected biomass projected. This analysis showed that if the 2022 recruitment resulted in 65 per cent less age 2 fish – because recent median recruitment has been lower than 65 per cent – a fishing mortality rate of 0.07, instead of 0.11, would be required to rebuild the stock by 2032 with 61 per cent confidence.

Canada is working on enhancing cooperation with the U.S. to better ensure the rebuilding of the Northwest Atlantic mackerel stock. To date, Canadian senior officials have advocated to U.S. colleagues the importance of coordinated action for rebuilding the stock while also providing Canadian data to help U.S. decision makers. The U.S. has indicated an openness to discussing the establishment of more formal cooperation and discussions are at the exploratory stage.

2.0 Stock status and stock trends

In 2003, the Privy Council Office, on behalf of the Government of Canada, published a framework applicable to all federal government departments. This framework sets out guiding principles regarding precautionary decision-making standards in situations where there exist risks of serious or irreversible harm due to a lack of full scientific certainty.

A Fisheries Decision-Making Framework Incorporating the Precautionary Approach (PA Policy) was developed and applies where decisions on harvest strategies or harvest rates must be taken to determine Total Allowable Catch (TAC) or other harvest control measures. The framework applies to key harvested stocks managed by DFO: those stocks that are the specific and intended targets of a fishery, whether in a commercial, recreational, or subsistence fishery. In applying the framework, all removals of these stocks from all types of fishing must be taken into account.

The following are the primary components of the generalized framework:

• Reference points and stock status zones (Healthy, Cautious, and Critical);
• Harvest strategy and harvest decision rules; and
• The need to take into account uncertainty and risk when developing reference points and developing and implementing decision rules.

The Atlantic mackerel stock limit reference point (LRP) was established through the Assessment of the Atlantic Mackerel Stock for the Northwest Atlantic (sub-areas 3 and 4) in 2016. This reference point defines the Critical-Cautious Zone boundary and is based on a proxy for spawning stock biomass (SSB) at maximum sustainable yield (MSY). The proxy for SSB_msy is SSB reference (SSB_ref) corresponding to the biomass at F_40%, a proxy for F_msy. F_40% is derived from a yield per recruit analysis and is the fishing mortality rate (F) that reduces the SSB per recruit to 40 per cent of its unfished level. This fishing mortality reference point is commonly used for small pelagic fish and was proposed during the 2010 meeting of the Canada-U.S. Transboundary Resources Assessment Committee and is consistent with the U.S. approach to science advice.

The upper stock reference point (USR), which defines the Cautious-Healthy Zone boundary, was recommended in the 2019 assessment and as part of the Management Strategy Evaluation, and was established by ministerial decision in 2022. It is calculated using default guidelines of 80 per cent of SSB_ref.

Table 2: Summary of the Precautionary Approach Framework reference points for Atlantic mackerel Scomber scombrus.

Notes:

1. ^A The limit reference point (LRP) and upper stock reference (USR) for this stock are set at 40 per cent and 80 per cent of SSB_ref, respectively. The reference points for Atlantic mackerel are derived from a spawner-per-recruit (SPR) model. The SSB_ref is the SSB at F_40%SPR (sometimes referred to as simply F_40%) and is considered a proxy for SSB_msy. Reference points for this stock are model specific. Therefore, specific values may change upwards or downwards with each new assessment.

The Atlantic mackerel northern contingent is assessed on a biennial basis using an age-structured model. Key data sources include landing statistics from Canada and the U.S., catch-at-age structures, and an egg production index. The model provides estimates for reference points and the stock parameters as well as other outputs (i.e., SSB, exploitation rate, etc.).

The model outputs (Figure 6 to 9), from the February 2023 Canadian stock assessment, illustrate that SSB decreased below the stock’s LRP for the first time in 2011 (Figure 6). SSB has since remained in, or near, the Critical Zone with its lowest SSB values of 40 per cent and 42 per cent of the LRP in 2021 and 2022, relative to 79 per cent and 56 per cent of the LRP in 2019 and 2020, respectively.

The last notable recruitment event occurred in 2015 (Figure 7), but in 2021 and 2022 this age group only represented a minor fraction (3 per cent or less) of the stock. The age structure of the stock has collapsed, compared to the pre-2000s, which coincides with a time of high fishing mortality (Figure 8). The stock recruitment relationship also indicated that large recruitment events are highly dependent on the stock biomass when the stock is at lower levels (Figure 9).

The mean probability of the SSB surpassing the LRP by 2025 ranges from 37.5 per cent under a TAC of 0 mt to 17.5 per cent under a TAC of 8,000 mt. The mean probability that the SSB will increase by 2025 ranges from 78.5 per cent under a TAC of 0 mt to 32.5 per cent under a TAC of 8,000 mt. Projections include a range of possible future removals of northern contingent fish by the U.S.^{Footnote 17}.Projections explicitly acknowledge that the rate of rebuilding is thus influenced by environmental conditions, determining for instance fish recruitment, but also U.S. mackerel harvest rates.

2.1 Committee on the Status of Wildlife in Canada (COSEWIC)

This stock has not been assessed by COSEWIC and is therefore not currently under consideration for listing under the Species at Risk Act.

2.2 Indigenous knowledge

DFO aims to incorporate Indigenous traditional knowledge and traditional ecological knowledge considerations in science processes as participants to peer-review meetings, and into fisheries management planning as members of the Atlantic Mackerel Advisory Committee (AMAC). DFO also holds discreet advisory sessions with First Nations and other Indigenous organizations, which serves as an opportunity to gather Indigenous knowledge. Furthermore, DFO is also interested in exploring additional and/or alternative methods to gather Indigenous knowledge.

3.0 Probable causes for the stock’s decline

Before the stock’s population decline into the Critical Zone in 2011, Atlantic mackerel spawning stock biomass (SSB) frequently fluctuated. These early oscillations are considered to be natural for small pelagic fish. Specifically, when large recruitment peaks drive rapid biomass increases, or conversely, when a subsequent decrease in recruitment, coinciding with the disappearance of a strong age group due to natural mortality, causes biomass to decrease significantly. The periodic arrival of dominant year-classes, such as those from 1967, 1974, 1982, 1988 and 1999, significantly influenced the age structure of Atlantic mackerel. Prior to the late 1990s, it was a common occurrence to catch mackerel that were 10 years or older. However, the gradual and inevitable removal of dominant year classes, due to fishing pressure resulted in a decrease in stock biomass. When biomass decreased, the exploitation rate was, however, not adapted accordingly and, therefore, estimated fishing pressure started to rise significantly from the mid-90s onwards. At the time, fishing pressure was still considered sustainable and natural mortality was thought to be the main driver of the observed biomass fluctuations.

Although SSB dropped to around the USR by 2000, a new recruitment peak (1999) drove another upsurge. This new and very dominant age group was estimated to have been overexploited between 2000-2006, due to an increase in fishing pressure and TAC levels that did not confine the fleets’ capacity to exploit the Atlantic mackerel stock. From 2005 onwards, science advice included recommendations to lower the TAC, the urgency of which increased over time. The TAC was, however, only reduced in 2010, and remained fairly constant from 2014 to 2020 (8,000 mt to 10,000 mt). In 2016, catches reached the TAC for the first time, and after the LRP was established in 2017, the stock’s status in the Critical Zone was confirmed. The stock was subsequently assessed to have been in, or near, the Critical Zone since 2011. The TAC was further reduced to 4,000 mt in response to the 2021 assessment of the Atlantic mackerel stock, as the age structure of the stock collapsed due to overexploitation, and SSB declined to 56 per cent of the LRP. Subsequently, the fishery closed in 2022 to allow the stock to rebuild, and this closure was extended in 2023.

Fishing pressure can be confounded with natural mortality. Recent evidence suggests that although the amount of Atlantic mackerel consumed by various predators increased over time, on average, this occurred gradually and did not correspond closely to the timing of the decrease into the Critical Zone. Based on the best available information, it is likely that the natural mortality rate increased as a result of both the increase in overall Atlantic mackerel consumption and, in particular, the decrease in SSB. Although natural mortality is unlikely a key cause of the stock’s decline, it is, at present, assumed that its increase might have contributed to the difficulty this stock has had to rebuild, and may continue to do so in the future. There is, however, no evidence that natural mortality is at a level that prevents rebuilding through fishery controls. Knowledge on Atlantic mackerel natural mortality will be updated if more, or updated, information becomes available (i.e., predator diet analysis, predator abundance estimates, etc.).

The stock’s decline is unlikely to have been caused by poor recruitment; although recruitment variance may have been reduced at the time, estimated values for that period were above average. Rather, the available evidence indicates that the decrease in SSB below the LRP caused a subsequent recruitment decline, and a diminished likelihood of observing important peaks. This slowed down rebuilding, and population growth became increasingly dependent on strong environmentally driven recruitment peaks. Such peaks are considered to be mostly the result of an optimal spatial and temporal match between Atlantic mackerel larvae and their prey, as well as Atlantic mackerel maternal body condition. There are, however, no indications that these indices (match-mismatch, condition) follow long-term trends, so that future environmental conditions do not appear particularly positive or negative for future recruitment. However, given the estimated low SSB, recruitment is –similar to natural mortality– assumed to hinder but not prevent rebuilding.

The stock’s decline was not affected by changes in Atlantic mackerel growth rate, as the average weight of fish at a given age remained largely unchanged over the last three decades. Loss or degradation of the stock’s fish habitat is also unlikely to have contributed to the stock’s decline given the current understanding of the best available evidence.

4.0 Measurable objectives aimed at rebuilding the stock

As outlined in the Precautionary Approach (PA) Policy and made obligatory under section 6.2(1) of The Fisheries Act, the primary objective of this rebuilding plan is to promote stock growth out of the Critical Zone (i.e., to grow the stock above the LRP with a high probability). The plan must consider the biology of the fish and environmental conditions affecting the stock, while ensuring removals from all fishing sources are kept to the lowest possible level until the stock has cleared this zone. Within the Critical Zone, this objective remains the same whether the stock is declining, stable, or increasing.

The rebuilding target, and secondary objectives for the rebuilding plan, as well as associated timelines, are outlined below. When the rebuilding target is reached, the long-term objectives for Atlantic mackerel will include further building the stock towards the Healthy Zone and maintaining the stock in this zone. These long-term objectives will be included in the IFMP once the stock has reached the rebuilding target.

4.1 Rebuilding target and timeline

Based on the PA Policy, the overarching objective for Atlantic mackerel is, therefore, for the stock to grow out of the Critical Zone. The rebuilding target for the plan will be to grow the stock so that it is above the LRP with a high likelihood (≥75% probability). This relative probability will ensure that the SSB is significantly above the LRP at the point where we consider rebuilt and is, therefore, less likely to slide back into the Critical Zone.

The timeline to rebuild a stock to its rebuilding target must be between T_min and a maximum of two to three times T_min, where T_min is the time the stock would take to rebuild to that target in the absence of all fishing (F=0) under prevailing productivity conditions. For Atlantic mackerel, the minimum time to rebuild was estimated by projecting 10 years into the future, using either F=0 or TAC=0. This latter scenario accounts for continued U.S. catches. Forecasts for T_min were calculated using five different operating models that reflect key framework uncertainties (i.e., variations from the base model in recruitment, natural mortality, and percentage of Canadian-spawned fish in U.S. landings) and which were already highlighted during the Management Strategy Evaluation^{Footnote 18} .

Under an F=0 scenario, the minimum time to grow the stock to above the LRP with a 75 per cent likelihood was estimated at 6 to 7 years. Under a scenario in which the U.S. would remove up to 3,639 mt (its 2023 commercial TAC) annually, this rebuilding time would increase to between 7 and 9 years. This inclusion of U.S. fishing in the T_min estimation is consistent with current U.S. catch of Atlantic mackerel which Canada has limited influence over. As such, the T_min for Atlantic mackerel is estimated to be 9 years and represents the minimum time required for the stock to rebuild above the LRP with a 75 per cent likelihood in the absence of Canadian fishing (TAC = 0) under prevailing productivity conditions. Prevailing productivity conditions for T_min estimation imply that near-future recruitment, mortality, or growth dynamics remain unchanged.

DFO will aim to rebuild the stock to the rebuilding target in 18 years (representing 2* T_min). This timeframe is within the required timelines specified in DFO’s Guidelines for writing rebuilding plans per the Fish Stocks Provisions and A Fishery Decision-making Framework Incorporating the Precautionary Approach. 2023 is considered year 1 of this timeline based on DFO Science projections starting in 2022.

During each review of the plan (see Section 8.0: Periodic Review of the Rebuilding Plan), the factors affecting the stock’s potential for growth will be reassessed to determine if their influence on the stock (or our perception thereof) has changed.

4.2 Additional measurable objectives and timelines

Under the PA Policy, while the stock is in the Critical Zone, management actions must promote stock growth, removals from all fishing sources must be kept to the lowest possible level, and there should be no tolerance for preventable decline. The additional objectives listed in this section provides an overview of the additional rebuilding objectives for the Atlantic mackerel stock. The purpose of these secondary objectives is to promote the primary objective of growing the stock above the LRP with a high likelihood. These secondary objectives aim to promote growth, improve monitoring, reduce post-discard mortality, increase bilateral cooperation with the U.S. and provide fishing opportunities. The timeline, for these secondary objectives, outlines a periodic review every two years while rebuilding the stock, and will focus on the impacts of implemented management measures, whether there is improvement in the stock status and the overall state of the ecosystem.

Additional measurable objectives and timelines aimed at rebuilding the Atlantic mackerel stock:

1. Promote a positive stock growth trajectory over a 2-year period with a minimum 75 per cent probability (based on most recent science advice)
   Timeline: Ongoing and reviewed every 2 years with the review of the rebuilding plan.
2. Improve monitoring
   Timeline:Started in 2023 and ongoing; reviewed with the rebuilding plan every 2 years. The first review will be in 2025, in line with the next new stock assessment.
3. Enhance measures to reduce post-discard mortality
   Timeline:Ongoing and reviewed with the rebuilding plan every 2 years.
4. Enhance scientific knowledge, and Indigenous Traditional Knowledge where possible, in the fields of stock structure, spawning dynamics, abundance, distribution and migration, and environmental conditions impacting the stock, including predation
   Timeline:Continued and reviewed with the rebuilding plan every 2 years. Increased bilateral cooperation/co-ordination with the United States (U.S.)
5. Increased bilateral cooperation/co-ordination with the United States (U.S.)
   Timeline:Ongoing and reviewed every 2 years with the review of the rebuilding plan.
6. Provide fishing opportunities while achieving stock rebuilding objectives
   Timeline:Ongoing and reviewed every 2 years with the review of the rebuilding plan.

5.0 Management measures aimed at achieving the objectives

Multiple management measures are required to rebuild the stock and achieve the additional objectives identified in Section 4.2. These measures and expected outcomes are presented below. They are informed by the numerous DFO Sustainable Fisheries Framework (SFF) policies such as the Precautionary Approach, bycatch and catch monitoring policies.

Objective 1 – Promote a positive stock growth trajectory over a 2-year period with a minimum 75 per cent probability (based on most recent science advice)

Management measure(s)

• Maintain fishing effort at levels consistent with this objective, and supporting the primary objective.

Expected outcome

• These measures are expected to keep removals at the levels that promote rebuilding.

Biology or environmental conditions taken into account

• Based on the requirements stated in the PA framework for stock in the Critical Zone.
• Stock assessments have indicated that overfishing has led to a collapse in the age structure with few older and more fecund fish. There have also been no signs of a substantial recruitment event since 2015.
• Therefore, limiting removals of Atlantic mackerel is likely to assist in rebuilding the age structure, leading to a positive growth trajectory.

Objective 2 – Improve monitoring

Management measure(s)

Continue implementation of the Fisheries Monitoring Policy (FMP), through the following:

• Complete Step 2 (Assessment of Monitoring Program) and present to AMAC in February 2024;
• Complete Step 3-6 (Setting Monitoring Objectives, Specifying Monitoring Requirements, Implementing Monitoring Programs, and Reviewing The Program) by spring 2025;
• Work in conjunction with stakeholders and partners to advance actions above, via the Rebuilding Plan Working Group;
• Update AMAC annually on FMP implementation.

Areas for further examination in response to FMP findings include:

• Explore feasibility of 100 per cent dockside monitoring for commercial and bait fisheries;
• Examine possibility of implementing hail-out in all regions (excluding those with VMS);
• Explore feasibility of hail-in for all regions;
• Explore options to improve collection of recreational catch and effort data;
• For the actions above, report on potential next steps to AMAC in 2025.

Expected outcome

• These measures will provide a concrete analysis that identifies monitoring needs and potential options to improve monitoring.
• The development of enhanced catch monitoring and compliance options will be the basis for continued work in subsequent versions of this rebuilding plan.

Biology or environmental conditions taken into account

• Stock assessment will include catch estimates using higher quality data inputs, improving advice.

Objective 3 – Enhance measures to reduce post-discard mortality

Management measure(s)

Explore new management measures that will limit discards, for example:

• Use of barbless hooks in line fisheries;
• Small fish protocol/move away provision;
• Reduce minimum size and, therefore, discards;
• Explore gear restrictions; and/or,
• Explore time/area closures;

For these actions, work would be conducted through the Rebuilding Plan Working Group, and a report to AMAC on potential next steps is anticipated for 2025.

Expected outcome

• These measures will provide a concrete analysis that identifies potential options to reduce discards and associated mortality.
• The development of options to reduce discard-associated mortality will form the basis for continued work in subsequent versions of this rebuilding plan.

Biology or environmental conditions taken into account

• Given the current age-structure of this stock, which features young fish predominantly, it’s especially important to minimize dead discards.

Objective 4 – Enhance scientific knowledge, and Indigenous traditional knowledge where possible, in the fields of stock structure, spawning dynamics, abundance, distribution and migration, and environmental conditions impacting the stock, including predation

Management measure(s)

Maintain programs for the stock assessment:

• Maintain adult sampling through the port sampling program (open fishery) or through S52-Licenses, in collaboration with industry from all DFO regions (closed fishery);
• Conduct an egg survey in the southern Gulf at the time of spawning, on a regular basis;
• Perform or support additional work to answer research questions as needed.

Expected outcome

Enhanced scientific knowledge should lead to:

• A greater understanding of stock dynamics and structure, including increased knowledge of environmental interactions and changes in predation/natural mortality;
• Reduced uncertainty in assessment model;
• Peer-reviewed publications;
• Improved advice for managers.

Biology or environmental conditions taken into account

• See section on ecosystems interactions.
• The impacts of climate change are addressed within enhancing knowledge of the environmental conditions impacting the stock.

Objective 5 – Increased bilateral cooperation/co-ordination with the U.S.

Management measure(s)

• Make use of engagement opportunities to pursue better-aligned management.
• Targeted DFO engagement of U.S. counterparts at the National Oceanic and Atmospheric Administration (NOAA) and the Mid-Atlantic Fisheries Management Council (MAFMC) on transboundary mackerel management. Engagement to occur at the working, science, and executive levels.

Expected outcome

• Establishment of on-going discussions to help develop conditions for coordinated actions on Northwest Atlantic mackerel.

Biology or environmental conditions taken into account

• The Hague line, which defines the international border between Canadian and U.S. waters, bisects the ecosystems in which Atlantic mackerel and other active fishery species migrate. As species distribution shifts due to climate change, forging a bilateral approach to managing transboundary stocks now would ensure joint management as ecosystem changes occur.

Objective 6 – Provide fishing opportunities while achieving stock rebuilding objectives

Management measure(s)

• Identify fishing opportunities for harvesters that do not jeopardize rebuilding goals. Opportunities may arise as part of scientific, personal-use bait, commercial, recreational, and FSC activities.

Expected outcome

• Continued provision of samples in scenarios where closures are in place.
• Potential economic benefits for harvesters.
• Alleviation of some bait needs in other Canadian fisheries.

Biology or environmental conditions taken into account

• Opportunities would need to align with stock rebuilding objectives.

6.0 Socio-economic analysis

The summary of economic contributions of Atlantic mackerel is presented in section 1.5 of this document. This section provides an analysis to assess the impacts of the management measures, including a fishery closure, on relevant harvesters and sectors. Since the closure of the Atlantic mackerel directed commercial and bait fisheries occurred in early 2022, the impacts of the closure occurred prior to the development of the Rebuilding Plan. As no new management measures are being proposed under this Rebuilding Plan, there will be no incremental impacts on commercial or bait harvesters, Indigenous communities, or recreational fishers.

Given the economic contribution of the Atlantic mackerel fishery and the number of harvesters involved, DFO acknowledges that the implementation of any new measures beyond those outlined here to further curtail and monitor the harvest of Atlantic mackerel may impact multiple sectors of the fishing industry. However, these cannot be assessed until such a time as the management measures are developed. Nonetheless, the overall dependency on mackerel was considered low for all mackerel fishing enterprises prior to the 2022 closure, as the species accounted for an average of less than 15 per cent of the landed revenues for the active harvesters. However, the impact of the moratorium may have been felt to a greater degree by the 52 enterprises that relied exclusively on mackerel with an average landed value of $6,757 in 2021 per enterprise prior to the moratorium.

As discussed in section 1.5, Atlantic mackerel is an important source of bait for other fisheries including lobster, crab, tuna, and halibut. The impact of the closure of Atlantic mackerel on bait supplies on fisheries that use mackerel as bait has not been evaluated due to lack of data on mackerel consumption. However, the value and quantity of lobster and crab landings over the last 10 years have continued to increase, suggesting lobster and crab harvesters did not experience any impacts due to lower domestic supplies of mackerel as bait. As mentioned in section 1.5, the price of mackerel has increased in recent years, and this could result in increased operating costs in fisheries that use mackerel as bait. The closure of the Atlantic mackerel commercial fishery could also result in some negative socio-economic impacts on fish harvesters, fish processing plant workers, and other value-added industries, particularly in communities that rely on Atlantic mackerel as a source of income. On the other hand, there could be positive impacts on fish harvesters and related industries in the future once the objectives of the Atlantic mackerel rebuilding plan are achieved and the fishery is reopened. However, these future impacts cannot be assessed in the absence of information on future TAC levels. Until such time as the current management measures are continued, there will be no incremental impacts on the stakeholders beyond those already experienced with the closure of the Atlantic mackerel commercial and bait fisheries in 2022.

7.0 Method to track progress towards achieving the objectives

Performance metrics provide DFO with a means to assess the progress of the rebuilding plan towards the plan’s objectives. For each objective, this section outlines how and when progress will be measured, either over the course of the entire rebuilding or the initial 2-year period prior to the first review.

Objective 1 – Based on most recent assessment, promote a positive stock growth trajectory over a 2-year period with a minimum 75 per cent probability.

Metric to measure progress

• Measure biomass in the terminal year of the current stock assessment relative to the biomass in the terminal year of the previous stock assessment.
• Ensuring the probability of projected growth in each stock assessment is in line with the objective and management measures continue to support the projected growth.

Frequency of measurement

• Stock assessments conducted and published over a 2-year cycle.

Objective 2 – Improve monitoring

Metric to measure progress

• Completion of FMP steps.
• Reporting on FMP implementation to AMAC.
• Development of options to improve monitoring for the consideration of AMAC.

Frequency of measurement

• Completion of FMP steps 1-2 by February 2024.
• Progress report to AMAC in 2024 and 2025.
• Options will be presented by the AMAC meeting in 2025.

Objective 3 – Enhance measures to reduce post-discard mortality

Metric to measure progress

• Initiatives to reduce and measure post-discard mortality will be developed in consultation with the RPWG in 2024 and an update will be presented to AMAC in 2025.

Frequency of measurement

• Options will be presented by the AMAC meeting in 2025.

Objective 4 – Enhance scientific knowledge, and Indigenous Traditional Knowledge where possible, in the fields of stock structure, spawning dynamics, abundance, distribution and migration, and environmental conditions impacting the stock, including predation

Metric to measure progress

• Completion and reporting of annual scientific surveys (egg surveys, adult sampling).
• Number of new research projects presented during the Atlantic mackerel assessment.

Frequency of measurement

• Stock assessments conducted and published over a 2-year cycle.
• New research findings published on the CSAS website or ISI peer-reviewed journals as they become available.

Objective 5 – Increased bilateral cooperation/co-ordination with the U.S.

Metric to measure progress

• Number of bilateral meetings held on mackerel.
• Number of letters to U.S. counterparts or submissions to U.S. mackerel management processes.
• International Council for the Exploration of the Sea (ICES) Working Group on Northwest Atlantic Mackerel Ecology and Assessment updates.

Frequency of measurement

• Annually via reports to AMAC.
• Approximately every 18 months.

Objective 6 – Provide fishing opportunities while achieving stock rebuilding objectives.

Metric to measure progress

• Metric tons that are harvested annually.
• Whether provided opportunities are consistent with rebuilding goals (based on most recent science advice).

Frequency of measurement

• At the end of each management cycle for Atlantic mackerel (i.e., every 1 or 2 years).

8.0 Periodic review of the rebuilding plan

The department will engage stakeholders on any matter related to the implementation/review of the rebuilding plan through the established Atlantic Mackerel Advisory Committee (AMAC) process. Outcomes from the application of this rebuilding plan will be monitored periodically, and a review will be undertaken every two years, which corresponds to each science stock assessment.

The review of the plan will be based on the data gathered using the metrics identified in the Method to Track Progress Towards Achieving the Objectives section of this plan. It will assess the progress of the implementation of management measures and evidence of their effectiveness, as well as the status of the stock and recent trends. In addition, the review will include opportunities for consultation with Indigenous groups and stakeholders on their views of the stock’s progress towards rebuilding.

The review process will generate a report that evaluates progress towards each management objective against their timelines with accompanying evidence and may propose adjustments to the rebuilding plan if necessary to achieve the objectives.

Stock rebuilding is not always a slow and steady, or even predictable process. Stocks may fluctuate and/or persist at low levels for years until conditions promote surplus production, resulting in rapid growth of the population. Thus, lack of progress towards rebuilding may not be an indication that the rebuilding plan’s objectives or management measures are insufficient or ineffective.

References

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Annex A - Income dependency analysis

Table A.1: Atlantic mackerel harvester’s fishing income dependency on mackerel, 2021 ^A

Notes:

1. ^A Values do not add up due to rounding. Also, minor variances appear in the formulas noted in the table due to rounding.
2. ^B The number of crew members for each enterprise is estimated by using an average of four (4) crew members (including licence holders and hired harvesters) per mackerel fishing enterprise in the Maritimes and Newfoundland and Labrador regions; and an average of two and a half (2.5) crew members (including licence holders and hired harvesters) per mackerel fishing enterprise in the Gulf and Quebec region. Numbers may not sum due to rounding.
3. ^C The average fishing income dependency is an average of the dependency ratios of all individual enterprises. That is, each of the 753 mackerel fishing enterprises has an income dependency ratio on mackerel, and the average dependency ratio for all of these 753 enterprises is 14.8 per cent.