Rebuilding plan for Atlantic mackerel – NAFO Subareas 3 and 4

1.0 Foreword

Fisheries and Oceans Canada (DFO) has developed “A Fisheries Decision-Making Framework Incorporating the Precautionary Approach” (PA Framework) 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 Framework requires that when a stock has reached or fallen below a limit reference point (LRP), a rebuilding plan must be put in place with the aim of having a high probability of the stock growing above the LRP within a reasonable timeframe.

The purpose of this rebuilding plan is to identify the main objectives and requirements for Atlantic mackerel in NAFO subareas 3 and 4, as well as the management measures that will be used to achieve these objectives. This document also serves to communicate the basic information on the Atlantic mackerel stock and its management to DFO staff, First Nations and other Indigenous organizations, and other fishery interests. This plan provides a common understanding of the basic “rules” for rebuilding the stock(s). The objectives and measures outlined in this plan are applicable as long as the stock is below the LRP or until an updated plan is completed. Once the stock grows and remains consistently above the LRP, the stock will be managed through the standard Integrated Fisheries Management Plan (IFMP) process. Management measures outlined in this rebuilding plan are mandatory, and may be modified to include additional catch restrictions if they fail to result in stock rebuilding.

This rebuilding plan is not a legally binding instrument which can form the basis of a legal challenge. The plan can be modified at any time and does not fetter the Minister's discretionary powers set out in the Fisheries Act. The Minister can, for reasons of conservation or for any other valid reasons, modify any provision of the rebuilding plan in accordance with the powers granted pursuant to the Fisheries Act.

Where DFO is responsible for implementing a rebuilding plan in an area under a land claim agreement, the rebuilding plan will be implemented in a manner consistent with that agreement.

Signed: Director General, Fisheries Resource Management, National Capital Region

2.0 Biological synopsis

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 contingents (spawning groups; Sette 1950): the southern (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 in the southern Gulf of St. Lawrence in June and July (Fig. 1). After spawning, northern contingent mackerel undertake an extensive feeding migration throughout Atlantic Canada and Québec waters from July to October, after which they migrate south to Sable Island, NS and into U.S. waters to mix with the southern contingent during late fall and winter.

200 mile fishing zone and NAFO fishing boundaries. For details, see description that follows.
Figure 1: Northern contingent population of Atlantic mackerel
Description

A map showing NAFO subareas and divisions. The northern contingent population of Atlantic mackerel (Scomber scombrus) are managed in NAFO subareas 3 and 4.

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 (Ware and Lambert 1985). 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 (Ware 1977).

Changes in mackerel distribution, recruitment, survival, and growth are known to vary with changes in temperature and the availability of prey (DFO 2019). Surface and bottom water temperatures have increased steadily across all of the northern contingent’s habitat since the late 1990s (Bernier et al. 2018). Zooplankton biomass, particularly that of Calanus finmarchicus, Atlantic mackerel’s preferred prey species, has also decreased throughout the Northwest Atlantic in recent years (Bernier et al. 2018). These environmental conditions (warming temperatures and the reduced availability of their preferred prey) have likely had a negative influence on mackerel recruitment and condition, both of which have been below average over the same time period (DFO 2019).

Atlantic mackerel, like other small pelagic fishes, play a critical role in the ecosystem by occupying central positions in aquatic food webs. That is, they are one of the key species for the transfer of energy from lower trophic levels (e.g. zooplankton) to higher order predators including a large range of fish, marine mammals, and sea birds (especially gannets). Although not considered the major prey source of grey seals (Halichoerus grypus; e.g., Bowen and Harrison 1994, 2006), diet analyses have shown an increase in mackerel at inshore sites in early winter (Bowen et al. 1993). Because of the central position of Atlantic mackerel in food web, variation in their abundance can affect both their prey and predators.

3.0 Overview of the fishery

Currently, the northern contingent supports an important commercial, bait, recreational and Indigenous Food Social and Ceremonial fisheries in the five eastern Canadian provinces (NAFO subareas 3 and 4) in spring, summer, and fall. During the winter, an unknown but possibly large proportion of the northern contingent overwinters in American waters and some are harvested in the commercial fishery in U.S. waters (NAFO subareas 5 and 6). A portion of the northern contingent fish may also overwinter in deeper warmer offshore waters at the edge of the continental shelf and would be unavailable to the fishery.

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 hand lines. The fishery grew rapidly after the development of improved salting techniques in the 1820s. By 1841, there were around 900 American vessels fishing for mackerel off the Atlantic coast. 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 mean combined Canadian and U.S. catches were around 34 500 t annually, reaching a high of around 106 000 t 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,  induced by power-driven  mobile gear harvesting.  

A large offshore foreign fleet, primarily from Eurasian countries, fished in North American waters from 1961 until 1978, in NAFO Division 3Ps and subareas 4, 5, and 6. Between 1970 and 1976, total catches of mackerel were upward of 240 000 t, reaching a maximum of nearly 420 000 t 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 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 foreign fleet that still captures mackerel in Subdivision 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 000t per year. Canadian landings reached a record high of 55 726t in 2005 due to the marked increase in fishing effort by small and large seiners on the east and west coasts of Newfoundland (divisions 3KL and 4R) and the presence of an exceptional 1999 year class. From 2000 to 2010, landings averaged 40 498 t. This was followed by a large drop in landings, reaching a low of 4 272 t in 2015. This decline was accompanied by poor recruitment over several years, and the loss of mackerel over 7 years old from the population. From 2016 to 2019, landings were 8 050 t (Total Allowable Catch (TAC) 8 000 t), 9 430 t (TAC 10 000 t), 10 499 t (TAC 10 000 t) and 8 405 t (TAC 8 000 t), respectively.

In DFO Maritimes, Gulf, Québec, and Newfoundland and Labrador regions (NAFO subareas 3 and 4), several hundred commercial fishers participate in the Atlantic mackerel fishery on a competitive basis.  They fish mainly inshore using gillnets, jiggers, handlines, seines, traps and weirs, depending on the region and the time of year. The majority of landings occur between  June and October.

Up to 1990, the three provinces with the largest landings were Nova Scotia, Prince Edward Island and Quebec. In the 1990s, the fisheries in the Gulf of St. Lawrence and Nova Scotia were predominant. 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 t three times between 2004 and 2010, representing 80% 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 from the mid-2000’s on 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 t to 29 161 t, and large seine landings from 6 074 t to 14 645 t. In more recent years, small seiners (purse, tuck and bar) have landed the majority of the catch in the commercial fishery.

Recreational fishing for Atlantic mackerel is practiced throughout Eastern Canada. Under existing regulations, a person may engage in recreational fishing for Atlantic mackerel by angling and no licence is required. The fishery is open all year round with no catch limits. However, fishing activities mainly occur during the summer months and there are gear restrictions. There is also a minimum fish size requirement consistent with the minimum size in the commercial fishery. DFO is working towards the implementation of regulations and limitations for the mackerel recreational fishery as part of the rebuilding initiative.

Fishing for bait is authorized by licence 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. The majority of this bait is used for tuna, lobster and crab fisheries.

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 Food Social and Ceremonial (FSC) Agreements between Indigenous groups and DFO that include access to mackerel for FSC purposes.

Governance/approval

DFO holds consultations at least every second year, or more often if needed, on Atlantic mackerel issues through the Atlantic Mackerel Advisory Committee (AMAC).  This Atlantic-wide Committee provides the main forum for representatives of industry, provincial governments, Indigenous organizations, environmental non-governmental organizations and other interested groups to provide input into the development of management measures for the mackerel fishery.

The Minister of Fisheries and Oceans delegates the authority for some approvals to national or regional staff but continues to retain final authority for fisheries management decision making.

The fishery is governed by a suite of legislation, policy and regulations including but not limited to those noted below.

4.0 Stock status

The northern contingent (or ‘Canadian’) mackerel stock is assessed bi-annually using an age-structured model. Key data sources include landing statistics, 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 (e.g. spawning stock biomass [SSB], exploitation rate, etc.). In accordance with the Precautionary Approach Framework, the limit reference point (LRP) and upper stock reference (USR) for this stock are set at 40% and 80% of SSBref, respectively. SSBref is determined based on F40%, a commonly used fishing mortality reference point used for small pelagic fish as a proxy for FMSY.

Atlantic mackerel has been assessed as being in the Critical Zone since 2011. High fishing mortality, low spawning stock biomass, and poor recruitment are the main factors hindering rebuilding the northern contingent.

During the 2019 stock assessment (DFO 2019), the 2018 SSB was estimated to be at 77% of the LRP, up from 59% in 2016 mainly due to a strong 2015 year-class. This 2015 cohort now dominates the landings as the population age structure is truncated, with few older fish. Recruitment in 2017 and 2018 was estimated to be at all-time lows. Estimated fishing mortality (including unaccounted for mortalities such as bait, recreation, discards) in 2018 was 1.13, which remained above the reference level of 0.68 (F40%). Short-term projections under different harvest control rules indicated that, with increasing commercial removals from 0 to 10 000 t per year, the probability of rebuilding the stock above the LRP by 2021 decreases from 68% at 0 catch to 48% at a 10 000t catch.

5.0 Socio-economic and cultural importance

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 $25.3M in 2005, with the expansion of the fishery in Newfoundland and Labrador. More recently, since 2013, the total annual landed value for Atlantic mackerel has averaged $7.4M, with a value of $10.8M, or 0.3% of total Canadian fish landed value, in 2017. Geographically in Canada, between 2013 and 2017, the landed value of the harvest has been distributed between Nova Scotia (29 % of the landed value), Newfoundland and Labrador (26 %), Prince Edward Island (20 %), Quebec (15 %), and New Brunswick (10 %). Of the approximately 600 fishing enterprises landing Atlantic mackerel in Canada, close to 70 percent of the enterprises fished for lobster as their main species. Detailed Atlantic mackerel landing information can be found on the DFO website.

Figure 2 Canada’s Atlantic mackerel landings, 2008-2017. For details, see description that follows.
Figure 2: Canada’s Atlantic mackerel landings, 2008-2017
Description

Figure 2 shows a combined line and bar graph which plots the value and quantity of Canada’s Atlantic mackerel landings from 2008 to 2017. The bar graph depicts quantity, measured in thousand tonnes, and the line graph depicts value, measured in millions of Canadian dollars. The quantity of landings falls from 29.7 thousand tonnes in 2008 to 9.5 thousand tonnes in 2017. The value of landings falls from 11.9 million dollars in 2008 to 9.5 million dollars in 2017. Both quantity and value peak in 2010 reaching 38.7 thousand tonnes valued at 18.5 million dollars. There is a steep decline in 2011 with quantity plummeting to 11.5 thousand tonnes valued at 10.9 million dollars. Between 2011 and 2017, Canada’s Atlantic mackerel landings depict a bowl-shaped trend with quantity and value bottoming out in 2014 and 2015, respectively, then recovering in 2016 and 2017. Quantity is the lowest in 2015 when it dropped to 4.1 thousand tonnes. Value is the lowest in 2014 when it reached 5.0 million dollars.

A significant quantity of Atlantic mackerel harvested commercially is used as source of bait in other fisheries. Harvesters use mackerel for a wide variety of different commercial species including lobster, crab, tuna, and halibut, which compounds the economic importance of mackerel.

Indigenous fishery

A number of Indigenous communities in Eastern Canada have access to Atlantic mackerel for Food, Social and Ceremonial (FSC) purposes. For centuries, harvests and use of fish by Indigenous communities has had important food, social and cultural significance and value to Indigenous peoples. When Europeans first arrived in Canada, a number of Indigenous communities were already harvesting mackerel. The reflection of some of these aspects (such as 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.

On the commercial communal fishery side, a total of seven Indigenous communities reported landings of mackerel between 2013 and 2017. For privacy reasons, annual landings information have to be suppressed due to participation by only a small numbers of Indigenous groups throughout the years. However, all landed weights and values for Indigenous fisheries are included in total Canadian reported landings.

Recreational fishery

The recreational fishery for mackerel is practiced throughout Eastern Canada by many people, including tourists, at dockside or aboard charter vessels. Although 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. Atlantic mackerel caught in the recreational fishery cannot be sold and there is a general lack of data related to the landings and associated value of the recreational fishery. Surveys of recreational fishing in Canada can be found on the DFO website.

Trade profile

In 2018, Canada’s mackerel exports were valued at $3.2M, representing 0.05 per cent  of Canada’s total fish and seafood export value¹. Newfoundland and Labrador ($2.2M) and Nova Scotia ($0.6M) shared the majority (89 per cent by value) of Canadian mackerel exports. In most other provinces, landings from the commercial fishery are mostly retained for bait in other domestic fisheries. 

Between 2014 and 2018, Canada’s total export value of mackerel has seen a general and notable trend downwards, with considerable fluctuation in the intervening years. The sudden drop in value has been almost entirely accounted for by equivalent drops in quantity of mackerel exported.

Figure 3 Canada’s Atlantic mackerel exports, 2014-2018. For details, see description box that follows.
Figure 3: Canada’s Atlantic mackerel exports, 2014-2018
Description

Figure 3 shows a combined line and bar graph which plots the value and quantity of Canada’s Atlantic Mackerel Exports from 2014 to 2018. The bar graph depicts quantity, measured in thousand tonnes, and the line graph depicts value, as measured in millions of Canadian dollars. Although the quantity of exports remains the same in 2014 and 2018 at 1.7 thousand tonnes, there is considerable fluctuation in the interim years with quantity falling to as low as 0.5 thousand tonnes in 2017. Between 2014 and 2018, Canada’s total export value of mackerel shows a downwards trend. The value of exports fell from 6.1 million dollars in 2014 to 3.2 million dollars in 2018. Export value reached a low-point in 2017 at 1.3 million dollars.

Mackerel does not undergo significant processing before shipment. Generally, mackerel is frozen whole for delivery in both the bait and food markets for domestic or export sales. As of 2018, 91 per cent of Canada’s mackerel exports were frozen and 9 per cent were prepared or preserved.

The United States has consistently been a key export market for Canadian mackerel, other key export markets include China, Ukraine, and Bulgaria. Detailed mackerel trade information can be found on the DFO website.

6.0 Management issues

Fishing, unaccounted for mortalities (bait, recreational, discards), low spawning stock biomass, and poor recruitment are the main factors hindering the probability of rebuilding the mackerel stock. During the 2019 stock assessment, it was estimated that removal rates were exceeding the maximum removal reference (F>F40%, a commonly-used small pelagic proxy fishing mortality rate for FMSY) and that this had been occurring since around 1998 to the present (2018). Large removals around that time period coincided with the gradual truncation of the age structure representing significant declines in abundance of older mackerel (> 6 years) from the stock.

Some fishing activity takes place in the spring during pre-spawning and peak spawning. This could have some implications on the stock recruitment, however, the effect is difficult to quantify. The period of spawning starts around June 2, peaks around June 21 and ends around July 22 and it occurs predominately in the southern Gulf of St. Lawrence. 

As part of a transboundary stock shared with the United States, a portion of northern contingent mackerel overwinter in U.S. waters where they are subject to fishing by U.S. vessels. Preliminary results from ongoing otolith microchemistry studies with U.S. collaborators suggest that in some years a large proportion of U.S. catches may comprise Canadian-spawned fish. The level of fishing activity in the United States. for Canadian spawned Atlantic mackerel is a concern for this stock. There are ongoing Canadian/U.S. projects currently dealing with the question of population discrimination using both genomics and otolith microchemistry. While this stock is not co-managed, both Fisheries and Oceans Canada and U.S. National Oceanic and Atmospheric Administration (NOAA) scientists have participated in the most recent stock assessments undertaken by both countries and therefore there is a common scientific understanding of stock status in both jurisdictions. In addition, an International Council for the Exploration of the Seas (ICES) Working Group on mackerel is being convened in 2021, which will include both Canadian and NOAA participants working on the northwestern Atlantic stock.

It has been identified that better accounting for all sources of mortality would improve the management of this fishery. Since 2017, in conjunction with industry, DFO has implemented a number of changes and improvements in catch monitoring and reporting to ensure a more complete catch database and there are ongoing efforts to continue to eliminate unreported catch.

In addition to high mortality, which includes both accounted for and unaccounted for fishing mortalities, the Northwest Atlantic ecosystem is undergoing significant changes that may impact mackerel as this species has strict habitat requirements. Analyses in the 2019 stock assessment suggest that mackerel recruitment, condition, seasonal migrations and distribution are heavily influenced by the availability and quality of food within their habitat. In recent years, availability and quantity of food sources have changed in magnitude, timing, and distribution which is likely impacting recruitment. Zooplankton changes in their distribution and biomass are likely driven by large-scale climatic changes and there are no available management measures for habitat restoration (food supply) for Atlantic mackerel.

Demand for bait is very high and mackerel is an important bait source. Low availability of bait and increasing prices may increase the incentive for illegal fishing of Atlantic mackerel.

7.0 Objectives

The Atlantic Mackerel Rebuilding Plan Working Group was established in December 2017 to bring representatives from DFO, provincial governments, industry stakeholders, aboriginal partners and others with an interest in the fishery together to improve the management of the Atlantic mackerel fishery in Atlantic Canada for the long-term sustainability of the stock. Work included the initiation of a Management Strategy Evaluation (MSE) process through which potential management measures and strategies could be evaluated in a systematic fashion to guide the discussions regarding management of the mackerel resource and future harvest control rules.  

The Atlantic Mackerel Rebuilding Plan Working Group tested several objectives through the MSE exercise which were used to inform management in evaluating the overall short- and long- term management objectives for rebuilding the stock. The following short-term objective has been developed through the rebuilding plan process:

The short-term objective for this stock is to limit the probability of Atlantic mackerel spawning stock biomass declining from one year to the next (i.e., maintain a positive growth trajectory).

It is important to note that over the last several years, since the establishment of the working group, the department has initiated a number of new management measures to support rebuilding. Some of these management measures include a 20% reduction in total allowable catch in 2019, enhanced measures to protect spawners, improvements in catch monitoring and reporting, and increased funding for science. It is expected that these rebuilding management measures will improve understanding of the stock and allow for more fully accounting of removals of Atlantic mackerel. Management measures are outlined in more detail in section 9 which details measures developed to support the rebuilding objectives for this plan.

Impacts from these management changes likely won’t be realized for several years, and therefore, progress toward rebuilding in the short term is expected to be incremental. As outlined in the guidance document for rebuilding plans in the critical zone, some flexibility in setting the rebuilding timeframe is desirable from a socio-economic perspective. Such flexibility allows for a management approach that promotes slow, yet  positive, stock growth with fewer socioeconomic impacts. The management approach adopted in this plan will promote rebuilding for this fishery by enhancing management of the resource and improving science, while allowing limited participation in the fishery.   

Progress towards meeting the short-term objective of a positive trajectory in the SSB in relation to the LRP will be evaluated over a 5-year period. Specifically, progress will be assessed in 2021, 2023, and 2025 when new stock assessments are to be completed for Atlantic mackerel and the working group will meet to discuss appropriate future measures based on the results. These milestone evaluations will provide a valuable and measurable indicator and assist the working group to make adjustments as required to ensure that rebuilding is on track.

The Long-Term objective of this stock is to rebuild Atlantic Mackerel Spawning Stock Biomass above the Limit Reference Point (goal to rebuild mackerel SSB).

Results from the MSE process, as outlined below, indicate that the timeframe on which this longer term objective can be achieved is beyond the duration of the rebuilding plan itself. While the goal remains to rebuild the stock above the Limit Reference Point within 10 years (by 2030) with a high probability, there is uncertainty in establishing that specific timeline for the longer-term objective, however, rebuilding out of the critical zone is expected to take longer than 10 years even with no commercial fishing. This is in large part because the US manages the stock independently and could continue to take an important fraction of the stock even in the absence of a Canadian commercial fishery. DFO will seek opportunities to engage with the U.S. on options for joint science and cooperative management. The working group will continue to evaluate progress in terms of meeting short and long-term objectives over the next 5 years and update the lifespan of the rebuilding plan as required.

Management Strategy Evaluation

A Management Strategy Evaluation (MSE) focusing on rebuilding strategies for the stock was conducted between 2017 and 2019, with a modelling framework and results finalized after the 2019 stock assessment.  All operating models in the MSE, used to represent different possible hypotheses about stock recruitment, natural mortality, and the proportion of northern contingent fish caught in the U.S. fishery, indicated that the stock continues to be below its LRP.

Candidate harvest control rules (HCRs) were evaluated at regular intervals (i.e., as milestones to track progress towards rebuilding and as longer term objectives). Specifically, HCRs with a different minimum TAC (see below) were evaluated over 3, 5 and 10 years.

Table: Candidate harvest control rules
MP HCR Minimum TAC Notes
1 F=0 0t This MP produces a baseline of stock potential rebuilding, when there are no fisheries removals (no implementation error)
2 No TAC 0t This MP produces a baseline of stock potential rebuilding, to be explored with different levels of implementation error (where actual fishing mortality varies above 0)
3 Simple Egg Index None TAC is calculated each year based on the relative change in the egg survey biomass estimate
4  
 
 
 
 
Target Egg Index
0t
(increase: alinear)
 
 
 
 
 

The HCR calculates TAC each year according to the figure.

In the rule, TAC is capped at a maximum of 25,000 t once the 3-year running egg survey average reaches Itarget.

5 0t
(increase: jump)
6 0t
(increase: ramp)
7 2,000t
8 4,000t
9 6,000t
10 8,000t
11 10,000t

Very few HCRs tested met the objectives developed to date, and no single HCR met all objectives under all uncertainty scenarios, mainly as a result of the current stock state and productivity, as well as the large uncertainty in total removals. The HCR that most closely reflected the 2019 Canadian TAC of 8 000 t failed to meet all candidate performance thresholds for all objectives and shorter-term milestones.  Simulation also showed that catches of 6 000 t to 10 000 t over the next 3 to 10 years were progressively more likely to result in stock declines than increases. According to the MSE, baseline estimates of stock rebuilding capacity (Tmin, or the time to rebuild with no fishing) indicated that time to rebuild the SSB above the LRP with high (>75%) probability ranges from at least 7 years (under conditions of no fishing mortality, F = 0) to greater than 10 years (under conditions of unaccounted-for mortalities but with commercial Canadian TAC = 0 t) under all core uncertainty scenarios.

The main conclusion of the 2019 MSE analysis was that the stock is unlikely to rebuild above the LRP with high probability (>75%) within the next 10 years if the catches, which include Canadian TAC and unaccounted-for mortalities, remained near recent levels.

The 2019 MSE results also indicated aspects of the fishery that could be considered or approached differently in analyses in the future, depending on information availability. This includes key uncertainties such as the proportion of U.S. catches that contain northern contingent mackerel, and the quantity of unaccounted-for mortalities in northern contingent mackerel catches. The results further indicated that future recruitment was important to the rate of rebuilding and future stock status.

8.0 Management measures

Since 2018, the department has introduced a number of new management measures to promote  rebuilding of the Atlantic mackerel stock out of the Critical Zone. A reduction in fishing activity in 2019, in combination with implementation of other management measures, will support efforts to rebuild this stock out of the Critical Zone.

The following management measures were put in place to improve our understanding of the stock and support rebuilding as part of the short-term objective to maintain a positive growth trajectory in the stock.

Catch reductions and controls

The primary control on fishery removals of Atlantic Mackerel is the TAC. From 2001-2009, the TAC was reduced to 75 000 t and in 2010 reduced to 60 000 t per year with further reductions to 36 000 for 2012 and 2013.  Catches reached a high of approximately 55 000 t per year between 2004 and 2007 inclusive but dropped to an average of less than 37 000 t per year from 2008-2010 and significantly declined to 11 401 t in 2011. At no time during the period from 1987 to 2014 did catches reach the established TAC level. In the past 5 years, the TAC has ranged between 8 000 t and 10 000 t per year. In the 2016, 2018 and 2019 fishery, the TAC was reached and the fishery closed in September or early October in each of those years.  In 2017, the fishery was temporary closed in mid-November to allow a review of landings which were nearing TAC and there was only limited activity following the re-opening so the full TAC was not reached.

In 2019, the department reduced the TAC by 20% in line with the stock assessment concerns about lack of recruitment in the stock.

In addition, a temporary freeze on the issuance of new commercial mackerel licences for fixed and mobile gear was implemented in July 2017 to eliminate the introduction of any new or additional fishing pressures. This includes the prohibition of existing participants adding new gear types to existing commercial licences that could result in increased capacity.

During the lifespan of this rebuilding plan the department will recommend both increasing controls as well as commercial harvest levels that are expected to promote positive growth (increases) in SSB.

Protecting spawners

A reduction in the removal of juvenile (small) fish aims to increase the productivity of the resource and encourage stock growth. Setting the minimum fish size to L50 allows a minimum of 50 % of the fish to spawn at least once before being targeted by the fishery. The minimum fish size increased from 250 mm to 263 mm in 2014 and another increase to 268 mm in 2019. The latest minimum size was established by the 2019 stock assessment based on the revised L50.

Since 2018, the opening date for the commercial fishery in the southern part of the Gulf of St. Lawrence was moved back from May 15th to June 1 to limit the removal or disturbance of fish before the spawning period in the key spawning area.

Recreational fishery – Atlantic Fishery Regulations, 1985 amendment

A regulatory amendment is proposed to prevent illegal fishing while still allowing true recreational harvesters the opportunity to fish recreationally for mackerel.

The recreational fishery for Atlantic mackerel is currently unregulated: there is no mechanism for catch reporting, and there are no fishing limits. This activity is practiced throughout eastern Canada by many people, including tourists at wharf or aboard vessels.

It has not been uncommon for some recreational vessels to land more than 500 lbs of Atlantic mackerel in a day with no reporting requirements. The absence of a recreational fishing limit creates the potential for commercial-scale fishing to continue under the guise of a recreational fishery, after the commercial fishery has been closed. In 2016, 2018 and 2019, when the commercial Atlantic mackerel fishery was closed early as quota had been filled, DFO did not have a mechanism to close the recreational fishery. This may have undermined the effectiveness of the commercial fishery closure. Since there are no enforceable measures when fishers claim to be taking part in the recreational fishery, it has proven challenging to document instances of unauthorized sales and to lay charges for this under the Fisheries Act.

The proposed regulatory amendment to the Atlantic Fishery Regulations, 1985 would establish a yearly close time from January 1 to March 31 and would also set a daily personal limit (20 fish) for recreational purposes. The change would address the currently unregulated and unlimited fishery and a loophole which has allowed some commercial/bait licence holders to land significant quantities of mackerel under the guise of a recreational fishery. It would also eliminate commercial harvesters from avoiding having to report all landings and the associated costs of dockside monitoring that is required for commercial fishing operations.

Better knowledge of catches, including putting limits on recreational catches, will support rebuilding of the stock. Better accounting of all harvests has becoming more important in recent years when the commercial total allowable catch has been fully utilized.

Catch monitoring and reporting

Catch monitoring and reporting of all landings was identified as a concern by management and science in stock assessments dating back a decade. The level of monitoring still varies by DFO Region for the commercial Atlantic mackerel fishery but there are mechanisms now in place for all commercial fisheries that better ensures all landings harvested under a commercial or bait licences are being reported.

All DFO Regions have been working with their fleets to improve data quality since 2017. A number of additional monitoring measures have been adopted over the last several years including introduction of additional dockside monitoring in Regions where they previously had none, 100% hail-in and increased frequency of reporting.

The majority of commercial landings are reported through logbooks and there is mandatory third-party verification using dockside monitoring for more than 60 percent of all landings. The department is also exploring implementation of mandatory measures for the reporting and submission of logbooks for the 2020 season. These measures could include limiting renewal of a licence if licence conditions related to logbook reporting are not followed.

An electronic logs (e-logs) project was initiated in the Mackerel fishery in 2018 and will continue through 2020 in the Quebec Region to provide more accurate and timely reporting of catch and effort information. It is anticipated that the e-logs program will be introduced in other Regions over the coming years to further improve the timeliness and accuracy of catch monitoring capabilities in all DFO Regions.

Bait fishery

DFO has implemented a number of measures to reduce the amount of unaccounted for mortalities in the bait fishery and will continue to build on these. Implementation of daily maximum limit on mackerel at 2 000lb per day in licence conditions is now in place for most bait licences. DFO will continue to focus on measures which will require mandatory hail-out in Regions where this is not already in place, increased enforcement of logbook reporting and, possible closure of the bait fishery when the commercial fishery closes.

Sampling and genetic testing

DFO provided additional funding devoted to scientific sampling and genetic analyses of Atlantic mackerel since 2018. The additional sampling provides missing information on the mackerel catch size distribution in areas where no data have been available for stock assessment purposes. The funding also includes the analysis of biological metrics that feed into the estimation of Spawning Stock Biomass. Genetic research is focused on the origin of young of the year mackerel in NL and the population structure of Atlantic mackerel in Canadian waters. A better understanding of the stock is important in providing management with more complete view of stock status.

Coordination with the U.S.

DFO will seek opportunities to engage with U.S counterparts on options for increased joint science and the introduction of cooperative management of the stock. The level of fishing activity in the U.S. for Canadian-spawned Atlantic mackerel is a concern for the future sustainability of this stock. Canadian rebuilding protections, including a TAC reduction, could prove negligible if many of the same mackerel could still be harvested when they migrate south in the winter months. Science provided a preliminary estimate that perhaps 50 per cent of mackerel caught in the U.S. winter fishery may be from the northern contingent (Canadian spawned).  The US currently has recently been establishing a TAC in their fishery that is double the recent Canadian established levels.  Over the longer-term history of this stock, Canada and the US had traditionally established TACs at the same levels even in the absence of any agreement or bilateral discussions.

9.0 Access and allocation

The TAC is currently reviewed every one or two years and adjusted where necessary in accordance with scientific recommendations and following consultations with industry and other interests. The commercial Atlantic mackerel fishery is a fully competitive fishery. There are no sharing arrangements currently in place or implemented either by province, region, gear type or vessel size.

DFO manages fisheries in a manner consistent with the constitutional protection of Indigenous and treaty rights.

The Minister can, for reasons of conservation or for any other valid reasons, modify access, allocations and sharing arrangements, in accordance with the powers granted pursuant to the Fisheries Act.

10.0 Shared stewardship

The department will continue to promote stewardship of the resource through stakeholder participation at advisory and working group meetings. The Atlantic Mackerel Rebuilding Plan Working Group, established in 2018, will continue to meet at least every two years to evaluate rebuilding objectives and consult on management measure for the fishery. The Atlantic Mackerel Advisory Committee will continue to be the consultative body that provides information and advice to the Department and Minister for fisheries management decision making.  

11.0 Compliance

Conservation and Protection Program description

The Conservation and Protection (C&P) Program promotes and maintains compliance with legislation, regulations and management measures implemented to achieve the conservation and sustainable use of Canada’s aquatic resources and the protection of species at risk, fish habitat and oceans.

The program is delivered through a balanced regulatory management and enforcement approach including:

Regional Compliance Program delivery

C&P promotes compliance with the management measures by the following means:

C&P maintains a strong monitoring, control and surveillance field presence.  An integrated approach is taken using existing and new technologies and strategies for the best use of available resources. Integration of VMS and the at-sea observer program information, closer monitoring of the dockside monitoring program and enhanced strategic responses are used to address compliance issues.

More specifically, compliance activities include:

Consultation

National Compliance Framework (Pillar 1)

Shared stewardship and education are encouraged through emphasis on the importance of communication with the community at large including:

Compliance performance

Types of violations
Type 2015 2016 2017 2018 2019 Total
Registration/licence 6 16 13 114 30 179
Species/size limit 3 9 16 27 10 65
Other legislation (i.e. Criminal Code, Wildlife Regulations) 21 3 16 4 7 51
Reporting 4 3 8 5 22 42
Illegal buy/sell/possess 5 4 11 8 18 27
Area/time 0 0 1 8 10 38
Gear – illegal/used illegally 3 3 1 3 5 15
Gear conflict 0 3 0 1 0 4
Illegal transportation 0 0 0 1 2 3
Assault/obstruction 0 0 1 1 0 2
Total 42 41 67 172 104 426

*the data abstracts above are from an operational system which is continually being updated and therefore subject to change

Current compliance issues

12.0 Evaluation and performance review

To ensure effective management of this fishery, regular reviews of management measures are required. In addition to annual internal reviews, there are two forums through which this takes place with stakeholders and other interests: the Atlantic Mackerel Advisory Committee and the Atlantic Mackerel Rebuilding Plan Working Group.

This Rebuilding Plan will be reviewed at least every two years as part of these forums. The periodic review of the rebuilding plan may include adjustments through the use of additional management measures if the plan’s short-term objective is not being met.

13.0 Reference

Bernier RY, Jamieson RE, Moore AM (eds). 2018. State of the Atlantic Ocean Synthesis Report. Can. Tech. Rep. Fish. Aquat. Sci. 3167: iii + 149 p.

Bowen WD, Harrison GD. 1994. Offshore diet of grey seals Halichoerus grypus near Sable Island, Canada. Mar. Ecol. Prog. Ser. 112:1-11.

Bowen WD, Harrison GD. 2006. Seasonal and interannual variability in grey seal diets on Sable Island, eastern Scotian Shelf. NAMMCO Sci. Publ. 6:123-134.

Bowen WD, Lawson JW, Beck B. 1993. Seasonal and geographic variation in the species composition and size of prey consumed by grey seals (Halichoerus grypus) on the Scotian Shelf. Can. J. Fish. Aquat. Sci. 50:1768-1 778.

DFO. 2019. Assessment of the Atlantic Mackerel stock for the Northwest Atlantic (Subareas 3 and 4) in 2018. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2019/035.

Sette OE. 1950. Biology of the Atlantic Mackerel (Scomber scombrus) of North America. Part II-Migrations and habits. Fish. Bull. Fish Wildl. Serv. 51:251–358.

Ware DM. 1977 . Spawning time and egg size of Atlantic mackerel, Scomber scombrus, in relation to the plankton. J. Fish. Res. Board Can. 34:2308-2315.

Ware DM, Lambert TC. 1985. Early life history of Atlantic mackerel (Scomber scombrus) in the southern Gulf of St. Lawrence. Can. J. Fish. Aquat. Sci. 42: 577-592.


¹ Canadian Trade Report by Species Group and Species, last accessed October 15, 2019