Rebuilding plan: Winter flounder, Pseudopleuronectes americanus - NAFO Division 4T

On this page

• Summary
• Acronyms used in this document
• Foreword
• 1.0 Introduction and context
  • 1.1 Population and distribution
  • 1.2 Biology
  • 1.3 Habitat requirements
  • 1.4 Ecosystem interactions
  • 1.5 Fishery
  • 1.6 Overview of the fishery socio-economic and cultural importance
  • 1.7 Involvement of stakeholder and Indigenous groups in the development of the plan
• 2.0 Stock status and stock trends
  • 2.1 COSEWIC assessment/SARA considerations
  • 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 considerations
• 7.0 Method to track progress towards achieving the objectives
• 8.0 Periodic review of the rebuilding plan
• 9.0 References
• Annex 1
• Annex 2

Summary

A small scale directed fishery for winter flounder used to be carried out in the southern Gulf of St. Lawrence (sGSL), Northwest Atlantic Fisheries Organization (NAFO) Division 4T. The species was also captured as bycatch in the directed yellowtail flounder fishery, which occurs mainly around the Magdalen Islands. A Total Allowable Catch (TAC) at 1,000 t annually was set from 1996 to 2011. However, the TAC was reduced to 300 t in 2012 in response to the stock’s steady decline. As there were no signs of stock rebuilding since 2012, the TAC was further reduced to 150 t in 2022. In February 2023, a full closure of the commercial winter flounder fishery was announced. The yellowtail flounder fishery was also closed due to the high incidence of winter flounder bycatch and the precarious state of the yellowtail flounder stock.

Winter flounder in the sGSL has remained in the critical zone of the Precautionary Approach (PA) framework since 2006. While fishing mortality is believed to be the primary cause of initial decline of 4T winter flounder stock in the 1970s and 1980s, the recent threat limiting rebuilding is now high natural mortality. The causes of the high natural mortality are not fully known but available evidence supports the hypothesis that predation by grey seals is a major component of this increased natural mortality.

As outlined in the PA framework, the primary objective of this rebuilding plan is to promote growth of the sGSL winter flounder stock out of the critical zone, by ensuring that removals from all fishing sources are kept to the lowest possible level until the stock has cleared this zone. The rebuilding target for the plan will be to grow the stock so that it is above the Limit Reference Point (LRP) of 147,800 t with a high likelihood (≥75%).  If the rebuilding target can be reached, the long-term management objective under the Integrated Fishing Management Plan (IFMP) will be to sustain the stock’s growth toward the healthy zone and then maintain the stock’s spawning stock biomass (SSB) in that zone. Achieving and maintaining the SSB in the healthy zone would be to the benefit of all Canadians, including:

• harvesters
• sectors closely involved with the fishing industry
• coastal communities who depend on the resource for their livelihood

At the current high level of natural mortality, declines in average size and estimated size at 50% sexual maturity, there are no signs of improvements for the sGSL winter flounder stock. In addition, scientific knowledge on the generation time for this species and the sGSL stock is incomplete. These conditions are such that a rebuilding timeline to the rebuilding target cannot be calculated at this time. During each review of the plan, the factors limiting this stock potential for growth will be re-assessed to determine if they are still influencing the stock and whether a rebuilding timeline can be calculated. In the meantime, this rebuilding plan aims at minimizing, to the extent possible, further declines of the stock. This is to preserve the stock such that, should the prevailing conditions limiting the stock’s recovery change, the stock retains the potential to rebuild.

Guided by the PA framework, management actions set out in this rebuilding plan maintain low fishing mortality to support rebuilding while continuing to monitor and assess the stocks. This will be done through:

• Keeping removals from all sources to the lowest possible level by introducing new and/or more stringent management measures in all fisheries that catch winter flounder, including maintaining the closure of the directed fishery for winter flounder and the directed fishery for yellowtail flounder, which takes a high proportion of winter flounder as by-catch. These measures also take into account that the yellowtail flounder stock in NAFO Division 4T has been in the critical zone of the PA framework since 2009.
• Monitoring all sources of fishing mortality, including by-catches, and enforce compliance with current management measures.
• Continue and advance scientific knowledge in the fields of monitoring stock status, recruitment, environmental conditions, and those ecosystem factors that are likely to impact the stock’s recruitment, growth, habitat and health.

Acronyms used in this document

AFS

Aboriginal Fisheries Strategy

Bmsy

Spawning stock biomass (SSB) that results from harvesting over a long time at fishing mortality consistent with achieving Maximum Sustainable Yield

COSEWIC

Committee on the Status of Endangered Wildlife in Canada

CSAS

Canadian Scientific Advisory Secretariat

DFO

Fisheries and Oceans Canada

DU

Designated Unit as defined by the COSEWIC (species, subspecies, variety, or geographically or genetically distinct population that may be assessed by COSEWIC, where such units are both discrete and evolutionarily significant)

F

Fishing mortality, usually expressed as instantaneous rate or annual rate (finite)

FSC

Food, Social and Ceremonial fisheries by First Nations and indigenous organizations

FSP

Fish Stocks Provisions in the amended Fisheries Act (2019)

GGAC

Gulf Groundfish Advisory Committee

HCR

Harvest Control Rules also called Harvest Decision Rules

GSL

Gulf of St. Lawrence

IFMP

Integrated Fisheries Management Plan

LRP

Limit Reference Point at the critical-cautious zone boundary of the precautionary approach framework

M

Natural mortality, usually expressed as instantaneous rate or annual rate (finite)

NAFO

Northwest Atlantic Fisheries Organization

PA

Precautionary Approach

RR

Removal Reference is the maximum acceptable removal rate for the stock

RV survey

Research Vessel survey (scientific) conducted annually in September

SARA

Species at Risk Act

sGSL

Southern Gulf of St. Lawrence

SSB

Spawning Stock Biomass

t

Metric ton, which is 1,000 kg or 2,204.6 lbs

TAC

Total Allowable Catch

TRP

Target Reference Point determined by productivity objectives for the stock, broader biological considerations and social and economic objectives for the fishery

USR

Upper Stock Reference point at the cautious-healthy zone boundary

Foreword

In 2009, Fisheries and Oceans Canada (DFO) developed a Fisheries Decision-Making Framework Incorporating the Precautionary Approach (PA Policy)^{Footnote 1} under the auspices of the Sustainable Fisheries Framework^{Footnote 2}. 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 these rebuilding plans and establishes a timeline for each rebuilding plan’s development.

The purpose of this plan is to identify the main rebuilding objectives for winter flounder in the Northwest Atlantic Fisheries Organization (NAFO) Division 4T, 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 processes 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.

The Honourable Diane Lebouthillier, P.C., M.P.
Minister of Fisheries, Oceans and the Canadian Coast Guard

1.0 Introduction and context

1.1 Population and distribution

The distribution range of winter flounder (Pseudopleuronectes americanus) is limited to the western Atlantic Ocean. The species is found from Labrador in the north, to the state of Georgia in the south (Scott and Scott 1988). It inhabits mainly shallow coastal waters, although offshore populations are found in locations such as Sable Island and George’s Bank (Scott 1976). Some commercial catches are reported from the northern Gulf of St. Lawrence (North Atlantic Fishing Organization (NAFO) Division 4S) and off western Newfoundland (NAFO Division 4R), indicating their wide distribution throughout the Gulf.

Winter flounder in the southern Gulf of St. Lawrence (sGSL; NAFO division 4T) inhabit mainly shallow coastal waters and are limited to the Magdalen Islands and the southern parts of the Gulf:

• the Chaleur Bay
• the Shediac Valley Miramichi area
• Northumberland Strait
• St. George’s Bay

They tolerate a wide range of water temperatures and are capable of inhabiting sub-zero water conditions due to serum antifreeze proteins that lower the freezing point of their blood to about -1.4°C. Winter flounder do not leave the Gulf in winter or migrate to deep water; they overwinter in estuaries or coastal areas (DFO 2012).

Although catches have decreased through time, presence of winter flounder in the various areas has generally remained the same, though at much lower abundance levels, with the exception of the Shediac Valley and eastern Prince Edward Island and northern Magdalen Islands areas, which now have very few winter flounder caught in the Research Vessel (RV) survey conducted annually in September (Surette and Rolland 2019).

1.2 Biology

Winter flounder may grow up to 58 cm total length (TL) and attain 15+ years of age. Growth rates vary among geographical areas, with slower growth in the north than in the south of its distribution (Pereira et al. 1999).

The estimates of the size at 50% maturity for winter flounder around the Magdalen Islands vary considerably from year to year. Recent work has shown a decreasing trend in the size-at-maturity, from 22 to 24 cm for both sexes in the 1970s, to the present size of approximately 17 cm (Surette and Rolland 2019). While the trend is punctuated with some strong year effects, it is clearly visible and is consistent with those observed in other species in the sGSL.

In the northern range of winter flounder distribution, spawning occurs in late winter or early spring:

• April in Passamaquoddy Bay
• May and June in Newfoundland

There are no direct observations of spawning time in the sGSL. 

Winter flounder spawn nearshore. Collection of winter flounder eggs from the wild is difficult because of their adhesive and demersal nature. Female winter flounder release several hundreds of thousands of eggs that settle to the bottom, adhering to rocks and vegetation. Fecundity measurements indicate that in Newfoundland, 22-44 cm females can produce from 99,000 to over 2 million eggs (Pereira et al. 1999). The average number of eggs produced per females is about 500,000 (Scott and Scott 1988).

Hatching of the eggs occurs in 2 to 3 weeks, depending on temperature. Larvae are initially planktonic and drift in surface waters (DFO 2012). Metamorphosis, when the left eye migrates to the right side of the body and the larvae become “flounder-like”, begins around 5 to 6 weeks after hatching, and is completed by the time the larvae are 8-9 mm in length at about 8 weeks after hatching. They become increasingly bottom-oriented as metamorphosis approaches and settle on the bottom at length of 9-13 mm (Pereira et al. 1999).

Stock structure is a source of uncertainty for this species. Winter flounder have a discontinuous, nearshore distribution and some known traits, such as their adhesive eggs and the limited movement of tagged animals, suggest that there may be local breeding populations within NAFO Division 4T. Some degree of mixing may be expected due to the drifting pelagic larval stage and straying of adult winter flounder (DFO 2012).

Generation time has not been estimated for the NAFO Division 4T winter flounder stock. Based on work conducted on winter flounder stocks along the eastern shores of the United States (southern New England and Massachusetts), a generation time of 3.5 years is estimated and presented in FishBase^{Footnote 3}. However, Siskey and Frisk 2021 report high generation time values, ranging between 10-15 years. Assuming a slower growth rate for winter flounder in the sGSL (Surette and Rolland 2019) and fish reaching 50% sexual maturity at approximately 4 years of age (Beacham, 1982), the generation time should normally be around or a little higher than the age at 50% sexual maturity. More research is required to estimate the generation time for this stock.

1.3 Habitat requirements

Winter flounder have a wide salinity and temperature tolerance. It occurs in waters with salinity ranging from typically oceanic to brackish estuaries (4-30‰) and temperatures ranging between 0 and 25°C (Pearcy 1962). In the sGSL, the species is found mainly in shallow water along the coastline, usually in depths of 1.8 to 36.6 m, on muddy to moderately hard bottoms (Scott and Scott 1988). Young fish normally inhabit shallower water than older or larger fish. Winter flounder do not leave the Gulf in winter or migrate to deep water. Instead, they overwinter in estuaries or coastal areas (Hanson and Courtenay 1996, Darbyson and Benoît 2003). Winter flounder also concentrate on spawning areas of Atlantic herring and capelin, consuming their eggs in large quantities (Frank and Leggett 1984; Tibbo et al. 1963). The seasonal nearshore movements and the lack of evidence that winter flounder make extensive migrations have led to speculation that the sGSL may have several local stocks, partly linked through larval drift.

1.4 Ecosystem interactions

Winter flounder are sight feeders, feed mainly during the daytime and have been described as omnivorous or opportunistic feeders, consuming a wide variety of prey. Polychaetes and crustaceans (mostly amphipods) generally make up the bulk of the diet. They feed opportunistically on a variety of benthic organisms, mainly mollusks and small crustaceans. They also feed on the eggs of other spawning fish, in particular capelin and herring (DFO 2012). Winter flounder have been reported to cease feeding during the winter months (Pereira et al. 1999).

Adult winter flounder are preyed upon by a wide variety of predators including:

• Striped bass
• Spiny dogfish
• Sea raven

Cormorants, blue herons, and ospreys have also been cited as predators (Pereira et al. 1999). In recent years, grey seals have also been identified as a predator of winter flounder within the sGSL (Hammil et al. 2014).

1.5 Fishery

Text version

Map showing the the North Atlantic Fisning Organization (NAFO) divisions and subdivisions along the Canadian Atlantic coast from Newfoundland to Nova Scotia. Division 4T are used to define the boundaries of the southern Gulf of St. Lawrence winter flounder stock.

The Southern Gulf of St. Lawrence (sGSL) groundfish fishery targets 9 major stocks (Table 1), distributed and managed within the North Atlantic Fishing Organization (NAFO) Division 4RST and subdivision 4Vn (Figure 1). Since the early 1990s, unique management measures have been put in place to address the severe decline of many groundfish stocks, and in the worst cases their collapse, resulting in the introduction of moratoria and significant quota reductions.

Unfortunately, the outlooks for many of these stocks remain precarious, with 5 out of 9 stocks currently in the critical zone. Of these, 4 are prescribed in the Fishery (General) Regulations (section 69) and therefore subject to section 6.2 of the Fisheries Act and regulatory requirements (Table 1).

Four of these stocks have also been assessed by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as potential candidates for listing under the Species at Risk Act (SARA) (Table 1; both redfish species are being considered as one stock for the purpose of management).

Most groundfish stocks managed within NAFO Division 4T overlap in both space and time, which increases the likelihood of non-target groundfish species being caught incidentally in other directed groundfish fisheries. As management measures are being developed for specific fisheries, it becomes critical to consider all potential interactions and sources of fishing mortality. As several commercial groundfish fisheries are occurring in the sGSL (Table 1), winter flounder are caught in some of these fisheries, especially in the yellowtail flounder fishery. Winter flounder are also being caught as part of a recreational fishery or by First Nations for community harvesting, or for Food, Social and Ceremonial (FSC) purposes.

Table 1. Most common groundfish stocks harvested in the southern Gulf of St. Lawrence.

Atlantic Cod ¹, Gadus morhua

• Stock area (NAFO divisions): 4T - 4Vn
• Most recent fishery closure/moratorium: Since May 2009
• Stock in critical zone²: Since 1990
• Population assessed by COSEWIC²: Endangered, 2010

Atlantic Halibut, Hippoglossus hippoglossus

• Stock area (NAFO divisions): 4T - 4R - 4S

American plaice¹, Hippoglossoides platessoides

• Stock area (NAFO divisions): 4T
• Most recent fishery closure/moratorium: Since May 2017
• Stock in critical zone²: Since 1993
• Population assessed by COSEWIC³: Threatened, 2009

Greenland halibut (turbot or black halibut), Reinhardtius hippoglossoides

• Stock area (NAFO divisions): 4T - 4R - 4S

White Hake¹, Urophycis tenuis

• Stock area (NAFO divisions): 4T
• Most recent fishery closure/moratorium: Since January 1995
• Stock in critical zone²: Since 1995
• Population assessed by COSEWIC³: Endangered, 2010

Winter Flounder¹, Pseudopleuronectes americanus

• Stock area (NAFO divisions): 4T
• Most recent fishery closure/moratorium: Since February 2023
• Stock in critical zone²: Since 2006

Witch Flounder, Glypocephalus cynoglossus

• Stock area (NAFO divisions): 4T - 4R - 4S

Redfish, Sebastes fasciatus and Sebastes mentalla

• Stock area (NAFO divisions): Unit 1: 4RST and 3Pn4Vn (January to May)
• Population assessed by COSEWIC³:
  • S. mentella: Endangered, 2010
  • S. fasciatus: Threatened, 2010

Yellowtail Flounder, Pleuronectes ferrugineus

• Stock area (NAFO divisions): 4T
• Most recent fishery closure/moratorium: Since February 2023
• Stock in critical zone²: Since 2009

The Gulf Groundfish Advisory Committee (GGAC), which brings together harvesters, processors, Aboriginal groups, DFO and provincial government representatives from the 4 Atlantic Provinces and Quebec, provides advice and recommendations to the department for the management of commercially exploited Gulf of St. Lawrence groundfish stocks (NAFO Divisions 4RST, 3Pn and subdivision 4Vn). The advisory committee meets every 2 years and serves as a forum for sharing results of recent stock assessments, for industry stakeholders and right holders to address issues affecting groundfish fisheries, and, most importantly, for DFO to solicit input from committee members on key management decisions.

In 2017, a Groundfish - Gulf of St. Lawrence NAFO Subdivisions 3Pn, 4Vn and Divisions 4RST Integrated Fisheries Management Plan (IFMP)^{Footnote 4} was developed by DFO in consultation with the GGAC. The IFMP provides detailed operational management information pertaining to mixed groundfish fisheries in the sGSL, including the winter flounder fishery.  An update to the Gulf Groundfish IFMP is underway and will account for stocks that are subject to a rebuilding plan, as all management measures outlined in the plan will supersede or will be in addition to those in the IFMP.

1.6 Overview of the fishery socio-economic and cultural importance

A small scale directed fishery for winter flounder was carried out in NAFO Division 4T, however a moratorium was announced in February 2023 on directed fishing of the winter flounder in Division 4T. The species is also captured as bycatch in the directed yellowtail flounder fishery, which occurs mainly around the Magdalen Islands. A Total Allowable Catch (TAC) at 1,000 t annually was set from 1996 to 2011.  However, the TAC was reduced to 300 t in 2012 in response to the stock’s steady decline (Table 2). As there were no signs of stock rebuilding since 2012, the TAC was further reduced to 150 t in 2022.  In February 2023, full closures of the commercial winter flounder and yellowtail flounder fisheries were announced^{Footnote 5}. These measures, which were consistent with the Fisheries Act’s new FSP, were intended to limit removals from commercial fisheries in order to promote the growth of these stocks.

Table 2. Winter flounder reported landings (directed and bycatch fisheries combined), contribution of bycatch landings (%) and active harvesters in NAFO Division 4T, from 2011 to 2021.

2011

• TAC (t): 1000
• Quantity (t) (directed and bycatch combined)²: 315
• % as bycatch³: 43%
• Value ($) (directed and bycatch combined): $565,708
• Price ($/kg): $1.80
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 40
  • Québec Region only: 23

2012

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 304
• % as bycatch³: 51%
• Value ($) (directed and bycatch combined): $566,188
• Price ($/kg): $1.86
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 47
  • Québec Region only: 28

2013

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 206
• % as bycatch³: 71%
• Value ($) (directed and bycatch combined): $509,903
• Price ($/kg): $2.48
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 40
  • Québec Region only: 27

2014

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 181
• % as bycatch³: 76%
• Value ($) (directed and bycatch combined): $465,224
• Price ($/kg): $2.56
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 28
  • Québec Region only: 25

2015

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 205
• % as bycatch³: 55%
• Value ($) (directed and bycatch combined): $592,119
• Price ($/kg): $2.89
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 36
  • Québec Region only: 28

2016

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 232
• % as bycatch³: 59%
• Value ($) (directed and bycatch combined): $696,234
• Price ($/kg): $3.01
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 47
  • Québec Region only: 35

2017¹

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 218
• % as bycatch³: 73%
• Value ($) (directed and bycatch combined): $857,808
• Price ($/kg): $3.94
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 33
  • Québec Region only: 28

2018

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 128
• % as bycatch³: 65%
• Value ($) (directed and bycatch combined): $468,979
• Price ($/kg): $3.68
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 27
  • Québec Region only: 24

2019

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 161
• % as bycatch³: 74%
• Value ($) (directed and bycatch combined): $741,135
• Price ($/kg): $4.61
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 27
  • Québec Region only: 22

2020¹

• TAC (t): 250
• Directed landings
  • Quantity (t): Closed
• Bycatch landings
  • Quantity (t): 58
  • Value ($): 55, 109
• Total landings
  • Quantity (t): 58
  • Value ($): 55, 109
• Price ($/kg): 0.94
• Active harvesters: 52

2021¹

• TAC (t): 300
• Quantity (t) (directed and bycatch combined)²: 133
• % as bycatch³: 67%
• Value ($) (directed and bycatch combined): $696,049
• Price ($/kg): $5.22
• Active harvesters (directed fishery only)
  • Québec and Gulf Regions: 25
  • Québec Region only: 21

2022

• TAC (t): 150 (annual allocation for other commercial groundfish fisheries)

Catches and values data not available before the publication of the current rebuilding plan.

The decline in winter flounder abundance, the contraction of its distribution (Surette and Rolland 2019) and the reduced TAC in 2012 resulted in a major decrease of the available and profitable fishing grounds, with a contraction of the winter flounder directed and bycatch fisheries around the Magdalen Islands. The main purpose of the fisheries has been, and is still to, supply the market for bait in the lobster and snow crab fisheries.

During the years of 2011 to 2017, the average landing of winter flounder stood at 237 t but started to register a notable decrease in 2018, with an average landing of 140 t for the 2018-2021 period. Landings for the Gulf Region in particular have seen a decrease of more than 90% since 2015. The 2021 estimated landed value for the entire NAFO Division 4T fishing area was $696,049 (Table 2).

In 2021, harvesters from the Magdalen Islands area reported 89% of the 133 t of winter flounder landed (directed and bycatch combined) in NAFO Division 4T, followed by Gaspésie-Bas-St-Laurent with 11%. Harvesters from the Gulf Region accounted for less than 1% of total winter flounder catches.

Over the 2011 to 2021 time period, the bycatch of winter flounder in the yellowtail flounder commercial bait fishery has become more important in volume than the directed fishery. In 2021, the reported bycatch landings of winter flounder in the yellowtail fishery accounted for 67% (90 t) of the total landings (133 t) (Table 2). In terms of value, bycatch represented more than $500,000 in 2021 or 71% of the total landed value. On average, for the 2011-2021 period, the quantity of winter flounder caught as bycatch represented 84% of total landings of this species in the Magdalen Islands; the only landing area in the Québec Region to record winter flounder bycatch landings. For the Gulf Region, bycatch of winter flounder in other directed groundfish fisheries are negligible (i.e.: less than 1 t since 2015) compared to the Québec Region.

Winter flounder directed commercial fishing is undertaken by registered fish harvesters who hold multi-species groundfish licences with:

• fixed gear (gillnets, longlines and handlines)
• mobile gear (otter trawls and Danish/Scottish seines)
• or both

Many harvesters may also hold licences for crustaceans (lobster or snow crab) or for pelagic fish (herring and mackerel).

In 2021, there were 31 groundfish licence holders with a licence condition for winter flounder in the Québec Region alone. Of these licence holders, 21 caught the species during the 2021 directed winter flounder fishery, which represent 68% of the total number of licence holders. For the Gulf Region (NAFO Division 4T), four harvesters landed the species during the 2021 directed fishery, which resulted in a total of 25 active harvesters in the sGSL for that year (Table 2). 

A steady decline of active harvesters in the directed winter flounder fishery has been observed over the years, down from 40 in 2011 to 25 harvesters in 2021 for the entire sGSL (Table 2). The bulk of this decline was observed with the reduced number of harvesters in the Gulf Region, as the fishery is now mainly conducted around the Magdalen Islands in the Québec Region. The number of active harvesters for the Québec Region did not report the same level of decline, with numbers being stable around the average of 24 active harvesters for the 2017-2021 period (Table 3). The number of active harvesters in the yellowtail flounder directed fishery reporting bycatch of winter flounder, has remained stable between 16 and 18 harvesters for the same time series (2011-2021) (Table 3).

Table 3. Landing values in the directed yellowtail flounder fishery and number of active harvesters in NAFO Division 4T, from 2011 to 2021.  All active harvesters were from the DFO Québec Region.

2011

• Yellowtail flounder directed fishery: $254,677
• Bycatches
  • Winter flounder: $230,504
  • Windowpane flounder: $252,278
  • Other species: $71,007
• Total: $808,467
• Number of active harvesters (directed yellowtail flounder): 74

2012

• Yellowtail flounder directed fishery: $161,730
• Bycatches
  • Winter flounder: $293,910
  • Windowpane flounder: $139,006
  • Other species: $12,348
• Total: $606,993
• Number of active harvesters (directed yellowtail flounder): 18

2013

• Yellowtail flounder directed fishery: $218,457
• Bycatches
  • Winter flounder: $379,382
  • Windowpane flounder: $270,536
  • Other species: $8,532
• Total: $876,906
• Number of active harvesters (directed yellowtail flounder): 18

2014

• Yellowtail flounder directed fishery: $232,110
• Bycatches
  • Winter flounder: $369,908
  • Windowpane flounder: $195,329
  • Other species: $21,021
• Total: $818,368
• Number of active harvesters (directed yellowtail flounder): 17

2015

• Yellowtail flounder directed fishery: $332,858
• Bycatches
  • Winter flounder: $376,017
  • Windowpane flounder: $147,645
  • Other species: $16,514
• Total: $873,034
• Number of active harvesters (directed yellowtail flounder): 16

2016

• Yellowtail flounder directed fishery: $275,008
• Bycatches
  • Winter flounder: $492,444
  • Windowpane flounder: $135,917
  • Other species: $21,491
• Total: $924,860
• Number of active harvesters (directed yellowtail flounder): 17

2017

• Yellowtail flounder directed fishery: $574,861
• Bycatches
  • Winter flounder: $687,109
  • Windowpane flounder: $286,879
  • Other species: $13,110
• Total: $1,561,960
• Number of active harvesters (directed yellowtail flounder): 18

2018

• Yellowtail flounder directed fishery: $436,652
• Bycatches
  • Winter flounder: $357,246
  • Windowpane flounder: $93,613
  • Other species: $6,041
• Total: $893,552
• Number of active harvesters (directed yellowtail flounder): 18

2019

• Yellowtail flounder directed fishery: $603,214
• Bycatches
  • Winter flounder: $602,717
  • Windowpane flounder: $177,383
  • Other species: $15,747
• Total: $1,399,060
• Number of active harvesters (directed yellowtail flounder): 17

2020¹

• Yellowtail flounder directed fishery: $705,990
• Bycatches
  • Winter flounder: $511,358
  • Windowpane flounder: $282,402
  • Other species: $21,251
• Total: $1,521,001
• Number of active harvesters (directed yellowtail flounder): 17

2021¹

• Yellowtail flounder directed fishery: $820,816
• Bycatches
  • Winter flounder: $497,704
  • Windowpane flounder: $454,598
  • Other species: $12,360
• Total: $1,785,479
• Number of active harvesters (directed yellowtail flounder): 17

In 2021, 25 harvesters were active in the directed winter flounder fishery in NAFO Division 4T. Among them, 4 harvesters got more than 10% of their total income from this fishery^{Footnote 6}.

Over the 2011-2021 period, lobster represented on average 60% of the total landed value (all species harvested combined) for the 25 active harvesters targeting winter flounder. Pelagic fishes (herring and mackerel; 14%) were in second place, followed by groundfish other than winter flounder (8%), snow crab (6%) and molluscs with other species (5%). Winter flounder represented 7% of their landed value, all species harvested combined.

With regard to the directed yellowtail flounder fishery in 2021, it included 17 harvesters in Quebec, including 11 for whom this fishery accounted for more than 10% of their total landings^{Footnote 7}. On average, during this directed fishery, these 11 harvesters caught:

• $70,783 of yellowtail flounder
• $42,312 of winter flounder
• $39,055 of windowpane flounder
• $732 of other species

The directed yellowtail flounder fishery averaged 69% of their total landings. These harvesters, all residents of the Magdalen Islands, will be the most affected by the closure of directed fisheries for winter flounder and yellowtail flounder.

There is currently an authorized groundfish recreational fishery with access to winter flounder in the waters adjacent to the Maritime Provinces in the sGSL^{Footnote 8}. However, most participants in the annual recreational groundfish fishery are targeting Atlantic cod. There is also a spring-summer recreational groundfish fishery in the Saguenay Fjord, and Estuary and Gulf of St. Lawrence with potential access to winter flounder^{Footnote 9}.

Under the Aboriginal Community Fishing Licence Regulations^{Footnote 10} and Aboriginal Fisheries Strategy (AFS) agreements^{Footnote 11}, Aboriginal communities can catch winter flounder if they hold groundfish licences. Winter flounder can also be fished as part of the Aboriginal FSC fishery. FSC fisheries are managed, where licensed, under the Aboriginal Community Fishing Licence Regulations and AFS agreements. The species caught under FSC licence conditions are not allowed to be sold.

No removal estimates are available for winter flounder in any of the recreational, AFS and FSC fisheries.  However, due to the low abundance of the species and its concentration in specific coastal areas of the sGSL (mainly the Magdalen Islands), the catch amounts in these fisheries are likely to be minimal, if any (based on qualitative field observations obtained from Conservation and Protection fishery officers).

1.7 Involvement of stakeholder and Indigenous groups in the development of the plan

A first meeting was held on September 24, 2020, with industry stakeholders and Indigenous partners to discuss the rebuilding plan development process and to solicit participation in a Gulf Groundfish Rebuilding Plans Working Group that would assist the department in developing the plans. Due to Covid restrictions limiting face-to-face meetings, DFO developed a questionnaire outlining rebuilding objectives and proposed management measures as an alternative means to solicit input from stakeholders and rights holders. The questionnaire was sent to members of the Gulf Groundfish Rebuilding Plan Working Group on December 15, 2020. An information session with Indigenous partners was also held on January 26, 2021.

The purpose of the questionnaire was to initiate discussions and gather views on rebuilding options for four groundfish stocks, including winter flounder. Stakeholders were also invited to propose adjustments or alternatives to the management measures presented. Stakeholders and rights holders were invited to comment on the proposed objectives and rebuilding measures, and to recommend alternative or other rebuilding measures in addition to the management measures presented. Although consolidated comments were sought through the Gulf Groundfish Rebuilding Plan Working Group, any member from the fishing industry, First Nations or Indigenous organizations could provide individual written comments.

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 that set out guiding principles for the application of precaution to decision-making about risks of serious or irreversible harm where there is a lack of full scientific certainty.

A Fisheries Decision-Making Framework Incorporating the Precautionary Approach was developed (DFO 2009), and applies where decisions on harvest strategies or harvest rates for a stock must be taken to determine TAC or other measures to control harvests. 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
• The need to take into account uncertainty and risk when developing reference points and developing and implementing decision rules

Most of the reference points as defined by the Precautionary Approach Framework (DFO 2009) were estimated for the winter flounder stock (Table 4). In the absence of an acceptable surplus production model or stock and recruitment model, a proxy for Bmsy was defined as the spawning stock biomass of winter flounder during a productive period, 1973 to 1994. This period was chosen because the SSB was high and the SSB comprised an important number of older and larger fish. The average biomass over the productive period is 369,600 t. The upper stock reference point, defined as 80% Bmsy, corresponds to 295,700 t. The limit reference point (LRP) value from the model is estimated at 40% of Bmsy, which corresponds to 147,800 t (Surette and Rolland 2019). Based on this model, the NAFO Division 4T winter flounder stock has been below the LRP since 2006.

Since the comprehensive stock assessment is normally conducted every 5 years, an interim biomass indicator for the LRP was developed to report on the stock’s status without going through a full assessment.

Table 4. Summary of the Precautionary Approach (PA) Framework reference points for NAFO Division 4T winter flounder.

• Limit Reference Point (LRP): 147,800 t of spawning stock biomass (SSB) or a RV survey index of 6,609 t (3.82 kg per tow)¹
  • Source: Surette and Rolland 2019, DFO 2020
• Upper Stock Reference (USR): 295,700 t
  • Source: Surette and Rolland 2019
• Target Reference Point (TRP): Not available
• Removal Reference (RR): Not available

Text version

The biomass index for commercial sizes winter flounder (≥ 25 cm) has declined over much of the period from 1971 to 2021. Since 2004, the index has continued declining under the LRP threshold value. The value of the 3-year moving average of the index in 2021 was 1,606 t of trawlable biomass in September, equivalent to a catch rate from the survey of 0.93 kg per tow. The 3-year moving average of the index is therefore estimated to be 24% of the LRP value of 6,609 t.

In the latest assessment (Surette and Rolland 2019), it was indicated that the 3-year moving average of the research vessel (RV) survey biomass index for commercial-sized winter flounder (≥ 25 cm total length) would be used as the indicator of stock status in the interim years of the multi-year management cycle. This index is to be compared to the LRP value for this stock, adjusted to the scale of the biomass index which is not corrected for survey gear catchability. The re-scaled LRP is 6,609 t of trawlable biomass in September, equivalent to a catch rate from the survey of 3.82 kg per tow (Table 4).

The value of the 3-year moving average of the index in 2021 was 1,606 t of trawlable biomass in September, equivalent to a catch rate from the survey of 0.93 kg per tow (DFO 2022). The 3-year moving average of the index is therefore estimated to be 24% of the LRP, slightly above the 17% reported in the previous indicator update (DFO 2020) but, still within the critical zone of the Precautionary Approach for this stock (Figure 3).

There has been a decline in fish length, with proportions of fish larger than 25 cm now accounting for about 25% of RV survey catches, in contrast to 82% of the catches in the early 1970s (Figure 4). Mean length in the survey has declined from 30 cm to 20 cm over the period 1971 to 2016 (Surette and Rolland 2019).

Indices from the RV survey show that small (< 25 cm) winter flounder abundance has been generally stable through time, though there has been a decrease since the early 2000’s, whereas large (≥  25 cm) winter flounder abundance has declined over much of the entire time series (1971-2016), after a period of relatively high abundance in the early to mid-1970s (Surette and Rolland 2019).
Based on a population model, the estimates of natural mortality have recently increased for young fish (ages 2 to 4) and continually increased for older fish (aged 5+) (DFO 2017, Figure 4). 

A new population model for winter flounder is currently in development and should provide revised reference points. However, this revision is not expected to change the overall status or critical state of the stock. 

Text version

Mean lengths were at around 27 to 29 cm during the early portion of the survey time series (1971 to 1985), and then decreased to 24 cm from the mid-1980s to 22 cm in the early 2000s and 21 cm from 2006 to 2016. The proportion of fish larger than 25 cm has gradually decreased from 81.7% at the beginning of the time series to 24.6% from 2006 to 2016.

2.1 COSEWIC assessment/SARA considerations

This stock has not been assessed by COSEWIC and is therefore not currently under consideration for listing under SARA.

2.2 Indigenous knowledge

DFO aims to incorporate Indigenous traditional knowledge and traditional ecological knowledge considerations in science processes as participants to peer reviews meetings, and into fisheries management planning as members of GGAC. As required, indigenous knowledge is also gathered through consultations with First Nations and other Indigenous organizations.

3.0 Probable causes for the stock’s decline

While fishing mortality is believed to be the primary cause of initial decline of 4T winter flounder stock in the 1970s and 1980s, the recent threat limiting rebuilding is now high natural mortality (Surette and Rolland 2019). 

The decline of winter flounder average length in the September RV samples (Figure 3), the decline of estimated size at 50% maturity from 23 to 24 cm in the 1970s to 17 to 18 cm in recent years, and the decline in abundance indices of the previously abundant commercial sized group are elements consistent with a stock experiencing very high mortality levels (Surette and Rolland 2019). Finite natural mortality estimates for winter flounder are generally high and are estimated to have increased from 49% annual mortality during 1973 to 1977, to 64% in 2013 to 2016 in older winter flounder (age 5+) and from 38% to 60% for younger winter flounder (age 2 to 4). These changes are also consistent with the changes in productivity observed throughout the marine fish community of the sGSL (Benoît and Swain 2008; Swain and Benoît 2015).

Text version

Instantaneous natural mortality estimates for winter flounder have increased from 0.68 during 1973 to 1977, to 1.02 in 2013 to 2016 in older winter flounder (age 5+) and from 0.48 to 0.93 for younger winter flounder (age 2 to 4).

The estimated fishing mortality in from 2010 to 2016 is very low (< 3 %) compared to natural mortality, suggesting that fishing mortality has little impact on the population trajectory (Figure 5). However, the population model is at the scale of the entire sGSL whereas fishing activity is now largely restricted to the waters around the Magdalen Islands. Furthermore, it is suspected that an important portion of the stock lies in shallow waters that the RV survey cannot have access for sampling. It is possible that fishing has had more impact on winter flounder in the vicinity of the Magdalen Islands that is not perceived at the level of the entire sGSL stock (Surette and Rolland 2019).

At the scale of the sGSL, natural mortality now appears to be the dominant factor affecting stock status. The causes of the high natural mortality are not fully known but available evidence supports the hypothesis that predation by grey seal is a major component of this increased natural mortality (Surette and Rolland 2019). Population models incorporating grey seal consumption suggest that the winter flounder NAFO Division 4T stock is one of numerous groundfish stocks impacted by grey seal predation (Hammill et al. 2014, Swain et al. 2019).

Given the relatively low level of harvesting of winter flounder from fisheries throughout most of NAFO Division 4T, it is unlikely that current levels of reported landings will impact the stock significantly (Surette and Rolland 2019). However, the increasing demand for winter flounder for use as bait leaves the potential for under-reporting, supporting the need to ensure adequate monitoring of all removals.

Text version

Overall the level of fishing mortality is very low compared to that of natural mortality for the entire time series of 1973 to 2016, with values ranging from 0.01 (1%) to 0.048 (4.8%).

During the last full assessment in 2017 (Surette and Rolland 2019), the population was projected forward five years (2017 to 2021) assuming productivity conditions from 2012-2016 would persist over the period. Projected SSB in the absence of fishing declined slightly over the period from 74,700 t in 2017 to 73,800 t in 2021 (Surette and Rolland 2019). The index of abundance presented for the year 2021 corroborates with the projection and shows that the winter flounder stock is still below the LRP (DFO 2022). Long-term projections beyond 2024 are not available.

As a coastal species, fluctuations of winter flounder populations along the eastern North American coast have been variously linked to environmental gradients, overfishing, differences in the timing of settlement, and location (Manderson et al. 2006, Frisk et al. 2018). However, there is no scientific research or evidence, that loss or degradation of the sGSL winter flounder stock’s fish habitat have contributed to the stock’s decline.

4.0 Measurable objectives aimed at rebuilding the stock

4.1 Rebuilding target and timeline

As outlined in the Precautionary Approach framework (PA), the primary objective of this rebuilding plan is to promote stock growth out of the critical zone (e.g. grow the stock beyond the LRP), by 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. Based on the PA framework, the overarching objective for NAFO 4T winter flounder 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 (147,800 t) with a high likelihood (≥75%). If the rebuilding target can be reached, the long-term management objective under the IFMP will be to continue the stock’s growth toward the healthy zone and then maintain the stock’s SSB in that zone. This long-term objective would be to the benefit of all Canadians, including harvesters, those sectors closely involved with the fishing industry and coastal communities who depend on the resource for their livelihood.

At the current high level of natural mortality, declines in average size and estimated size at 50% maturity, there are no signs of improvements for the sGSL winter flounder stock (Surette and Rolland 2019, DFO 2022). In addition, scientific knowledge on the generation time for this species and the sGSL stock is incomplete and cannot be used. These conditions are such that a rebuilding timeline to the rebuilding target cannot be calculated at this time. During each review of the plan, the factors limiting the stock’s potential for growth will be re-assessed to determine if they are still influencing the stock, and if a rebuilding timeline can be calculated. In the meantime, and in compliance to the PA framework, this rebuilding plan still aims at minimizing, to the extent possible, further declines of the stock. This is to preserve the stock such that, should the prevailing conditions limiting the stock’s recovery change, the stock retains the potential to rebuild.

4.2 Additional measurable objectives and timelines

Under the PA framework, management actions must promote stock growth and removal from all fishing sources must be kept to the lowest possible level while the stock is in the critical zone, and there should be no tolerance for preventable decline. 

Table 5 provides an overview of the secondary rebuilding objectives for the NAFO Division 4T winter flounder stock, aimed at enabling DFO to monitor all sources of mortality, the impacts of implemented management measures, whether there is improvement in the stock status and the overall state of the ecosystem.

Table 5. Additional measurable objectives and timelines aimed at rebuilding winter flounder, NAFO Division 4T stock.

1. Secondary objectives: Keep removals from all sources to the lowest possible level by introducing new and/or stricter management measures in all fisheries that intercept winter flounder.
   • Timeline: Starting in 2023 and reviewed every 5 years with the review of the rebuilding plan.
2. Secondary objectives: Monitor sources of fishing mortality and enforce compliance of current management measures.
   • Timeline: Starting in 2023 and reviewed every 5 years with the review of the rebuilding plan.
3. Secondary objectives: Continue and advance scientific knowledge in the fields of monitoring stock status, recruitment, environmental conditions, and those ecosystem factors that are likely to impact the stock’s recruitment, growth, habitat and health.
   • Timeline: Continue and review the state of the stock every five years, in parallel with the review of the rebuilding plan.

5.0 Management measures aimed at achieving the objectives

Multiple management measures are required to achieve the objectives identified in Table 5.  These measures and expected outcomes are presented in Table 6. They are informed by the DFO Sustainable Fisheries Framework policies such as the Precautionary Approach (DFO 2009), bycatch (DFO 2013) and catch monitoring (DFO 2019) policies. Since the winter flounder (NAFO Division 4T) is unlikely to rebuild in the short term (i.e.: next 5 years) under prevailing conditions (see section 3.0 Probable causes for the stock’s decline), the objectives are aimed at preserving the stock such that should the prevailing conditions limiting the stock’s recovery change, the stock retains the potential to rebuild.

6.0 Socio-economic considerations

While a summary of economic contribution of winter flounder is presented in section 1.6 of this document, this section provides the basis to assess the impacts of fisheries closures on relevant harvesters. Since the closures of the winter flounder and yellowtail founder fisheries occurred in early 2023, the impacts of the closures occurred prior to this rebuilding plan. Therefore, no incremental impacts on harvesters are expected with the implementation of the plan.

Nevertheless, a perspective of the number of harvesters impacted from the 2023 fishery closures is estimated based on 2021 fishing effort data. In 2021, there was about 40 groundfish license holders with a condition for winter flounder or yellowtail flounder in the Gulf and Québec Regions (36 of these licence holders being in the Quebec Region). Of these licence holders, 25 were active and caught the species during a directed winter flounder fishery in 2021 (21 and 4 harvesters in the Quebec and Gulf Regions respectively). A total of 17 harvesters caught winter flounder as bycatch in the yellowtail flounder directed fishery.
In 2021, the 40 harvesters who were active in directed fisheries for winter flounder and yellowtail flounder landed $1.97 million during these 2 fisheries, including:

• $821,798 of yellowtail flounder
• $696,$557 of winter flounder
• $454,610 of windowpane flounder
• $19,411 of other species

It should be noted that winter flounder was caught exclusively during these 2 directed fisheries.

For 15 of these 40 harvesters^{Footnote 12}, the directed winter flounder and/or yellowtail flounder fishery accounted for more than 10% of their total fishing income in 2021. As shown in Table 7, these 15 harvesters generated revenues of $1.84 million from both directed fisheries for winter flounder and yellowtail flounder in 2021. It represented an average revenue of $123,005 per harvester, broken down by species as follows:

• yellowtail flounder ($51,973)
• winter flounder ($41,432)
• windowpane ($28,641)
• other species ($958)

For these 15 harvesters, the directed fisheries for winter flounder and yellowtail flounder represented, on average, 71% of their total income.

Table 7. Total and average landing values of the 15 fishers who were active in the directed winter flounder and/or yellowtail flounder fishery in 2021.

Species caught:

• Yellowtail flounder
  • Total value of landings: $779,599             
  • Average value of landings per harvester: $51,973
• Winter flounder
  • Total value of landings: $621,487             
  • Average value of landings per harvester: $41,432
• Windowpane flounder
  • Total value of landings: $429,617             
  • Average value of landings per harvester: $28,641
• Sculpins
  • Total value of landings: $7,229  
  • Average value of landings per harvester: $482
• Atlantic halibut
  • Total value of landings: $6,588  
  • Average value of landings per harvester: $439
• Atlantic cod
  • Total value of landings: $555      
  • Average value of landings per harvester: $37
• Grand total
  • Total value ($) of landings: $1,845,079   
  • Average value of landings per harvester: $123,005

The magnitude of the socio-economics impacts associated with the closure of the winter flounder and yellowtail (Quebec region only) directed fisheries cannot be accurately quantified at this point due to lack of relevant costs and earnings data. Assessing the impact is all the more complex since the fish caught during directed fisheries for winter flounder and yellowtail flounder are often used as bait in other fisheries (lobster, snow crab, etc.). The closure of these fisheries could thus result in increased operating costs in the fisheries that use these species as bait, which are already struggling with a problem of scarcity in other sources of local bait such as pelagic fish (herring and mackerel).

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, Table 8 outlines how and when progress will be measured.

Table 8. Summary of the performance metrics and frequency of measurement associated with each objective in this rebuilding plan.

1. Objective: Keep removals from all sources to the lowest possible level by introducing new and/or stricter management measures in all fisheries that intercept winter flounder.     
   • Metric to measure progress: Winter flounder reported landings do not exceed 150 t and originate only as bycatches from authorized groundfish fisheries.  
   • Frequency of measurement: Annually as part of the Gulf Region post-season review of all management activities and fisheries conducted in the sGSL (NAFO Division 4T).
2. Objective: Monitor sources of fishing mortality and enforce compliance of current management measures.       
   • Metric to measure progress: Qualitative assessment of the efficiency and efficacy of catch monitoring programs with the different fleets and harvesters.       
   • Frequency of measurement: Annually as part of a review of all management activities and fisheries conducted in the sGSL (NAFO Divisions 4T) (Gulf Region – Annual post season review)
3. Objective: Continue and advance current scientific knowledge in the fields of monitoring stock status, recruitment, environmental conditions, and those ecosystem factors that are likely to impact the stock’s recruitment, growth, habitat and health.         
   • Metric to measure progress: Conduct the September annual research vessel survey. Publish findings from science work (including a new stock assessment model and revised reference points) in CSAS research documents within the 5 years review cycle.  Some results may also be published in specialized scientific journals.      
   • Frequency of measurement: Regularly, as documents are peer reviewed and published on the CSAS website or in scientific journals.

8.0 Periodic review of the rebuilding plan

The department will engage stakeholders on any matter related to the implementation or review of the rebuilding plan through the established Gulf Groundfish Advisory Committee (GGAC) process.  Outcomes from the application of this rebuilding plan will be monitored periodically, and a thorough review will be undertaken every 5 years, corresponding to each comprehensive scientific assessment of the stock.

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.

With the development of a new stock assessment model for winter flounder in the sGSL and revision of the reference points, a review of the rebuilding plan before the scheduled 5-year interval may occur. The call for this review before 2027 will depend on DFO Science Branch success in developing a reliable model and the overall conclusions of the new information about the stock.

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.

9.0 References

• Benoît, H.P., and Swain, D.P. 2008. Impacts of environmental change and direct and indirect harvesting effects on the dynamics of a marine fish community. Can. J. Fish. Aquat. Sci. 65: 2088-2104.
• Beacham, T. 1982. Biology and exploitation of winter flounder (Pseudopleuronectes americanus) in the Canadian Maritimes area of the Northwest Atlantic Ocean. Can. Tech. Rep. Fish. Aquat. Sci. 1113. Fisheries and Oceans Canada, Ottawa
• Darbyson, E. and Benoît, H.P. 2003. An atlas of the seasonal distribution of marine fish and invertebrates in the southern Gulf of St. Lawrence. Can. Data Rep. Fish. Aquat. Sci. 1113. Fisheries and Oceans Canada, Ottawa
• DFO.  2009. A Fisheries Decision-Making Framework Incorporating the Precautionary Approach (April, 2009). 
• DFO. 2012. Assessment of Winter Flounder (Pseudopleuronectes americanus) in the southern Gulf of St. Lawrence (NAFO Div. 4T).
• DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2012/016.
• DFO.  2013. Policy on Managing Bycatch (April, 2013). 
• DFO. 2017. Stock assessment of Winter Flounder (Pseudopleuronectes americanus) of the southern Gulf of St. Lawrence (NAFO Div. 4T) to 2016. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2017/022.
• DFO.  2019. Fishery Monitoring Policy (November, 2019).
• DFO. 2020. Updated indices of abundance to 2019 for Winter Flounder from NAFO Div. 4T, Witch Flounder from NAFO Divs. 4RST and White Hake from NAFO Div. 4T. DFO Can. Sci. Advis. Sec. Sci. Resp. 2020/008.
• DFO. 2021. Stock Assessment of Yellowtail Flounder (Limanda ferruginea) of the southern Gulf of St. Lawrence (NAFO Div. 4T) to 2020. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2021/022.
• DFO. 2022. Updated index of abundance to 2021 for Winter Flounder from NAFO Div. 4T. DFO Can. Sci. Advis. Sec. Sci. Resp. 2022/025.
• Frank K.T. and W. C. Leggett W.C. 1984. Selective Exploitation of Capelin (Mallotus villosus) Eggs by Winter Flounder (Pseudopleuronectes americanus): Capelin Egg Mortality Rates, and Contribution of Egg Energy to the Annual Growth of Flounder. Canadian Journal of Fisheries and Aquatic Sciences. 41(9): 1294-1302.
• Frisk, M. G., T. E. Dolan, A. E. McElroy, J. P. Zacharias, H. Xu, and L. A. Hice. 2018. Assessing the drivers of the collapse of Winter Flounder: implications for management and recovery. Journal of Sea Research 141:1–13.
• Hammill, M.O., Stenson, G.B., Swain, D.P., and Benoît, H.P. 2014. Feeding by grey seals on endangered stocks of Atlantic cod and white hake. – ICES Journal of Marine Science, 71: 1332–1341.
• Hanson, J.M., and Courtenay, S.C. 1996. Seasonal use of estuaries by Winter Flounder in the southern Gulf of St. Lawrence. Trans. Am. Fish. Soc. 125: 705-718.
• Manderson, J. P., J. Pessutti, P. Shaheen, and F. Juanes. 2006. Dynamics of early juvenile Winter Flounder predation risk on a Northwest Atlantic estuarine nursery ground. Marine Ecology Progress Series 328:249–265.
• Pearcy, W.G. 1962. Ecology of an estuarine population of Winter Flounder, Pseudopleuronectes americanus (Walbaum). Parts I to IV. Bull. Bingham Ocean. Coll. Yale U. 18: 1-78.
• Pereira, J.J., R. Goldberg, J.J. Ziskowski, P.L. Berrien, W.W. Morse, and D.L. Johnson, 1999.  Essential fish habitat source document: Winter Flounder, Pseudopleuronectes americanus, Life History and Habitat Characteristics. NOAA Tech Memo NMFS NE 138; 39p.
• Rolland, N., Swain, D. and Ricard, D. 2022. The Status of Yellowtail Flounder (Limanda ferruginea) in NAFO Division 4T to 2020. DFO Can. Sci. Advis. Sec. Res. Doc. 2022/041. v + 82 p.
• Scott, J.S. 1976. Summer distribution of groundfish on the Scotian Shelf 1970-74. Fisheries and Marine Service Technical Report 635. iv + 51 p.
• Scott, W.B. and Scott, M.G. 1988. Atlantic fishes of Canada. Can. Bull. Fish. Aquat. Sci., 219: 1-731.
• Siskey, M.R. and Frisk, M.G., 2021. The Relative Influence of Age Structure, Predation, and Temperature on Stock–Recruitment Dynamics: A Case Study of Southern New England/Mid‐Atlantic Winter Flounder. Marine and Coastal Fisheries, 13(5), pp.583-599.
• Surette, T., and Rolland, N. 2019. Assessment of the Winter Flounder (Pseudopleuronectes americanus) stock of the southern Gulf of St. Lawrence (NAFO Div. 4T) to 2016 and advice for the May 2017 to May 2022 fisheries. DFO Can. Sci. Advis. Sec. Res. Doc. 2019/026. x + 94 p.
• Swain, D.P., and Benoît, H.P. 2015. Extreme increases in natural mortality prevent recovery of collapsed fish populations in a Northwest Atlantic ecosystem. Mar. Ecol. Prog. Ser. 519: 165 - 182.
• Swain D.P., Benoît, H.P., Hammill, M.O. and Sulikowski, J. A. 2019. Risk of extinction of a unique skate population due to predation by a recovering marine mammal. Ecological Applications 29(6):e01921. 10.1002/eap.1921
• Tibbo, S. N., Scarratt, D. J., and McMullon, P. W. G. 1963. An Investigation of Herring (Clupea harengus L.) Spawning Using Free-Diving Techniques. Journal of the Fisheries Research Board of Canada. 20(4): 1067-1079.

Annex 1

At-sea observer and dockside monitoring minimum requirements, and bycatch limits by fleet, fishing gear and target species in 2022-23

Halibut: Fixed gear – NAFO Divisions 4RST

• Fleet (vessel overall length and monitoring programs): < 13.71m at-sea observer: 10%, DMP: 100%
  • Target species: Atlantic halibut
  • Bycatch limits by species (% bycatch per fishing trip)
    • *Atlantic cod 4T: 30%
    • Greenland halibut 4RST: 5% (3% for ITQ fleets)
    • *White hake 4T: 5%
• *American plaice 4T: ¹
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 10%
• Fleet: < 13.71m at-sea observer: 5%, DMP: 100%
• Target species: Greenland halibut or turbot (gillnets)
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 10%
• Atlantic halibut 4RST: 3%
• *White hake 4T: 5%
• *American plaice 4T: ¹
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: 1%
• Other groundfish species 4T: 10%
• Fleet: >= 13.71m Gaspé, Québec Region at-sea observer: 20%, DMP: 100%, VMS: 100%
• Target species: Atlantic halibut
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 30%
• Greenland halibut 4RST: 5%
• *White hake 4T: 5%
• *American plaice 4T: ¹
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 10%
• Target species: Greenland halibut or turbot (gillnets)
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 10%
• Atlantic halibut 4RST: 3%
• *White hake 4T: 5%
• *American plaice 4T: ¹
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 10%
• Fleet: <19.81m Eastern New-Brunswick at-sea observer: 10% for vessels <13.71m and 15% for vessels >= 13.71m, DMP: 100%
• Target species: Atlantic halibut
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: Max daily limit 45kg or 30%
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *American plaice 4T: 10%
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 25%
• Fleet: <19.81m Magdalen Islands at-sea observer: 10%, DMP: 100%
• Target species: Atlantic halibut
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: Max daily limit 45kg or 30%
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 10%
• Fleet: <19.81m Gulf Nova Scotia at-sea observer: 10%, DMP: 100%
• Target species: Atlantic halibut
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: Max daily limit 45kg or 30%
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *American plaice 4T: 10%
• *Winter flounder 4RST: ¹
• Witch flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 25%
• Fleet: <15.24m Maritimes Region at-sea observer: 5-10%, DMP: 100%
• Target species: Atlantic halibut
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: Max daily limit 45kg or 30%
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *American plaice 4T: 10%
• *Winter flounder 4RST: ¹
• Witch flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 25%

Winter flounder: Fixed gear – NAFO Divisions 4RST

• Fleet: <19.81m at-sea observer: 5% with the exception of Québec’s fleet with a 10% coverage, DMP: 100%
• Target species: Winter flounder
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 5%
• Atlantic halibut 4RST: ¹
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *American plaice 4T: 10%
• Yellowtail flounder 4T: 25%
• Other groundfish species 4T: 10%

Yellowtail flounder: Mobile gear – NAFO Division 4T

• Fleet: <19.81m at-sea observer: 10% in groundfish fishing areas 4T2(a), 4T6 and 4T7 and the open portion of 4T3a will apply. 25% in groundfish fishing area 4T8 will apply. DMP: 100%
• Target species: Yellowtail flounder
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 10%
• Atlantic halibut 4RST: ¹
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *American plaice 4T: 10%
• *Winter flounder 4RST: 25%
• Witch flounder 4RST: 25%
• Other groundfish species 4T: 10%

Witch flounder: Mobile gear – NAFO Divisions 4RST

• Fleet: <19.81m at-sea observer: 25%, DMP: 100%
• Target species: Witch flounder
• Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 20%
• Atlantic halibut 4RST: ¹
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%
• *American plaice 4T: 10%
• *Winter flounder 4RST: 25%
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 10%

Redfish (index fishery): Mobile gear – Unit 1 (4RST, 3Pn, 4Vn)

• Fleet: <19.81m at-sea observer: 25%, DMP: 100%
  • Target species: Redfish
  • Bycatch limits by species (% bycatch per fishing trip)
• *Atlantic cod 4T: 5%
• Atlantic halibut 4RST: ¹
• Greenland halibut 4RST: ¹
• *White hake 4T: 10%, 5% for Québec fleet
• *American plaice 4T: 10%, 5% for Québec fleet
• *Winter flounder 4RST: ¹
• Yellowtail flounder 4T: ¹
• Other groundfish species 4T: 15%, 5% for Québec fleet

Annex 2

NAFO Division 4T winter flounder key management measures until the next review of the rebuilding plan in 2028.

Objective 1

Keep removals from all sources to the lowest possible level by introducing new and/or stricter management measures in all fisheries that intercept winter flounder.

• 2024 (considered to be year 1 of this rebuilding plan).
• Maintain the closure of the commercial directed fishery.
• Maintain the closure of the yellowtail flounder commercial directed fishery.
• Bycatch TAC = 150 t for each stock.
• Bycatch limit per trip = ranging between 10%¹ and 25%²
• 2025
• Maintain the closure of the commercial directed fishery.
• Maintain the closure of the yellowtail flounder commercial directed fishery.
• Bycatch TAC = 150 t for each stock.
• Bycatch limit per trip = ranging between 10%¹ and 25%²
• 2026
• Maintain the closure of the commercial directed fishery.
• Maintain the closure of the yellowtail flounder commercial directed fishery.
• Bycatch TAC = 150 t for each stock.
• Bycatch limit per trip = ranging between 10%¹ and 25%²
• 2027
• Maintain the closure of the commercial directed fishery.
• Maintain the closure of the yellowtail flounder commercial directed fishery.
• Bycatch TAC = 150 t for each stock.
• Bycatch limit per trip = 5%
• 2028
• Maintain the closure of the commercial directed fishery.
• Maintain the closure of the yellowtail flounder commercial directed fishery.
• Bycatch TAC = 150 t for each stock.
• Bycatch limit per trip = 5%

Objective 2

Monitor sources of fishing mortality and enforce compliance of current groundfish management measures.

• 2024
  • VMS (Vessel Monitoring System) not used in all NAFO 4T groundfish fisheries.
• 2025
  • VMS not used in all NAFO 4T groundfish fisheries.
• 2026
  • Use of VMS in all NAFO Division 4T groundfish fisheries.
• 2027
  • Use of VMS in all NAFO Division 4T groundfish fisheries.
• 2028
  • Use of VMS in all NAFO Division 4T groundfish fisheries.

If the objective set in the plan in terms of bycatch level exceeds its allocation, additional adjustment measures may be evaluated and implemented before the next planned review.