Atlantic cod, No rthern stock in Newfoundland and Labrador region

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1 Atlantic cod, Northern stock in Newfoundland and Labrador region, Longlines Content last updated 31st Jul 2017 Stock: Northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) Management: NAFO Atlantic cod, Northern stock in Newfoundland and Labrador region, Longlines Overview Atlantic cod (Gadus morhua) is a widely distributed roundfish that inhabits the waters of the North Atlantic Ocean, Arctic Ocean, Labrador Sea and Barents Sea most frequently at temperatures ranging from 0 to 12 C. In NAFO Divisions 2J3KL (Labrador and Newfoundland region), this species exists near the low end of the temperature range and exhibits relatively slow growth and late maturity with almost all females being mature by age 5. Mature adults form large spawning aggregations between winter and spring on the outer slopes of the continental shelf on Hamilton Bank usually at depths from 200 to 600 m. Each summer adults migrate large distances (up to 800 km) from their offshore spawning grounds on Hamilton Bank to inshore feeding areas mainly along the Labrador coast and northeast Newfoundland. Juveniles in the first two years of life are mainly found in nursery grounds in shallow coastal waters (< 30 m depth) where there are complex habitats providing protection from predators. Mortality rates have historically been very high, and the stock has been severely depleted since the early 1990s. Recruitment to the fishery occurs at around age 3. Cod mainly feed mainly on fish (e.g. capelin, Mallotus villosus) and invertebrates (e.g. Pandalus spp.), and can be cannibalistic especially at high population densities. Predators include other fish, marine mammals (e.g. Harp seal, Phoca groenlandica) and sea birds. A moratorium on directed fishing for northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) has been in place since Nevertheless, landings of northern cod in NAFO Divisions 2J3KL have averaged around tonnes per year between 1998 and Most of the fish have been taken in a small-scale inshore commercial stewardship fishery for cod and a recreational fishery for mixed groundfish species. Widespread discarding of small cod takes place in the recreational fishery both on land and at sea. The status of the northern cod stock in NAFO Divisions 2J3KL is poor with relatively low abundance, spawning stock biomass and recruitment since the early 1990s. Total mortality has declined to among the lowest levels on record since the introduction of multi-year management plan in the early 1990s. At the present time, this stock remains outside safe biological limits given that it has historically been harvested unsustainably. Management of this stock is by a permitted annual catch allowance per licence holder for NAFO Divisions 2J3KL. Stock Status less risk more risk The status of northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) has been scored a high risk. This is because abundance, spawning stock biomass and recruitment have been at low levels since the early 1990s despite a reduction in the total mortality rate. Although spawning stock biomass has increased considerably since 2006, it has remained well below the precautionary limit (B lim ) since the early 1990s. The stock biomass is currently at 34% of the limit reference point and remains within the critical zone. Total mortality rates have declined since The status of the stock has improved in recent years with abundance and spawning stock biomass increasing from low levels, but they are still much lower than observed at the peak of fishing activity during the 1980s. Consequently, this stock remains outside safe biological limits given that it has historically been harvested unsustainably and is currently suffering from reduced reproductive capacity. Management less risk more risk The management of northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) has been scored a low risk. This is because management decisions are informed by an annual stock assessment, catches of northern cod are controlled through a permitted annual catch allowance per licence holder, and a comprehensive regulatory framework is in place. Control measures have not been entirely effective in protecting the stock from overexploitation. Bycatch less risk more risk The bycatch impact of the set longline fishery for northern cod in NAFO Divisions 2J3KL has been scored a moderate risk. This is because bycatch of nontarget species in the set longline fishery is relatively moderate (15-39% of catch weight) compared to other fisheries in the world. Set longlines have the potential to take moderate quantities of bycatch of non-target species in certain circumstances. Seabirds are vulnerable to capture when longlines are being set and there is a risk of the capturing rays and sharks. Longlines can be adapted to minimise bycatch of non-target species by modifying the hook design and altering harvesting behaviour (e.g. operating at night when seabirds are less active). Habitat less risk more risk The habitat impact of the set longline fishery for northern cod in NAFO Divisions 2J3KL has been scored a very low risk. This is because set longlines are a passive form of fishing gear that has relatively little interaction with the seabed compared to other fishing activities. Set longlines can get entangled on habitat features and mooring weights/anchors can cause abrasion and penetration of the seabed. Outlook

2 Current risk status Outlook Reason Stock High Improving Although the biomass is increasing, it remains well below the limit reference point and within the critical concern score. Management Low Stable Management measures are in place and the biomass is increasing. Bycatch Moderate Improving The bycatch impact of the set longline fishery is likely to improve in the future. Technical and spatial management measures are continuously under development and will likely reduce the risk further. Habitat Very low Improving The habitat impact of the set longline fishery is likely to improve in the future. Technical and spatial management measures are continuously under development and will likely reduce the risk further. Type Current Risk Status Outlook Reason Stock Management Bycatch Habitat

3 Stock Status Details less risk more risk Time-trends A hotly contested international fishery for northern cod developed off southern Labrador and eastern Newfoundland during the 1960s and continued until the late 1970s (Brattey et al., 2010). Landings of northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) averaged around 502 kilo tonnes per year between 1962 and 1976 (Figure 1). During this period, northern cod migrating from offshore over-wintering areas into inshore feeding areas were mainly caught by a traditional inshore fixed-fishery. Catches of northern cod increased during the 1960s to a peak of over 800 kilo tonnes in 1968, declined steadily to a low of 140 kilo tonnes in 1978, increased to about 240 kilo tonnes through much of the 1980s, and then declined rapidly in the early 1990s in advance of the moratorium on directed fishing in 1992 (DFO, 2016). The biomass of the northern cod stock in NAFO Divisions 2J3KL was about 3 million tonnes in the 1960s (DFO, 2013). Fishing intensity increased greatly in the 1960s as non-canadian fleets exploited dense offshore over-wintering aggregations. The stock collapsed to about 0.5 million tonnes by the late 1970s. Landings of northern cod averaged around 212 kilo tonnes per year between 1977 and 1991 following Canada claiming jurisdiction of the 200 nautical mile Exclusive Economic Zone (EEZ) and prohibiting vessels from other countries fishing in the region. After the extension of jurisdiction in 1977, the stock began to recover with an increase in biomass to just over 1 million tonnes by the mid-1980s. Another decline in biomass was evident in the late 1980s with the stock collapsing to an extremely low level by the early to mid-1980s. The total mortality rate (Z, ages 4-6) was low in the 1980s, but increased to a high level from the early 1990s to the mid-2000s which impeded stock recovery. Total mortality declined substantially between 2003 and 2006, resulting in an expansion in the age composition which has been an important factor driving the recent increase in spawning stock biomass. The average fishing mortality rate in 2015 was 0.014, which is low (DFO, 201). Spawning stock biomass declined rapidly during the late 1980s and early 1990s, remained very low for two decades following the moratorium on directed fishing in 1992 and has increased since The spawning stock biomass, however, has remained below the precautionary limit (B lim ) since the early 1990s. Population abundance and biomass increased in the mid-2000s, declined between 2009 and 2011, and has since increased. Currently, population abundance and biomass are 28% and 24% of the average during the 1980s respectively (DFO 2016). By the 1990s, offshore populations of over-wintering cod were barely detectable but aggregations of cod inhabiting inshore feeding areas in Divisions 3L and 3K were apparent. These inshore populations were more productive than offshore populations during the 1990s. A small fishery directed at these inshore populations was introduced in Catch rates declined and the directed commercial fishery and the recreational fishery were closed in Northern cod were mainly taken as bycatch in the winter flounder (Pseudopleuronectes americanus) fishery between 2003 and Most of the catches of cod between 1993 and 1997 came from bycatch, food/recreational fisheries and DFO-industry sentinel surveys that began in In addition, catches from 1998 to 2002 came from a commercial inshore fishery restricted to fixed gear and small vessels (< 65 foot). Recruitment in the offshore component of the fishery during the 1990s and 2000s has been poor compared to the 1980s. The number of young fish (ages 3 and 4) in the autumn research survey in the 1990s has been consistently lower than during the 1980s, but year class strength increased slightly between 2002 and Recently, landings of northern cod in NAFO Divisions 2J3KL were 4,436 t in A commercial stewardship fishery for cod and a recreational fishery for groundfish were re-opened in 2006 and continued until Recreational landings of cod account for a substantial proportion of total removals of northern cod in NAFO Divisions 2J3KL. Tagging information indicates that removals of commercial size fish in the recreational fisheries during were approximately 30% of the removals from the commercial stewardship fishery. Currently, the northern cod stock in NAFO Divisions 2J3KL is at a low level and management actions have focused on promoting increases in spawning stock biomass and subsequent recruitment to increase the resilience of the stock to fishing activities (DFO, 2016). Stock structure and recruitment For assessment and management purposes, northern cod inhabiting the Newfoundland and Labrador region have been divided into three distinct sub-populations: Division 2J (south of Hopedale), Division 3K (north of Cape Freels) and Division 3L (Cape Freels Cape St. Mary). Tagging studies during the late 1990s and early 2000s indicated that inshore feeding areas were inhabited by at least two distinct groups of cod: (1) a resident coastal group that inhabited an area from Trinity Bay northward to western Notre Dame Bay; and (2) a migrant group that over-wintered in inshore and offshore areas of Subdivision 3PS, moved into southern Division 3L during late spring and summer, and returned to subdivision 3PS in the autumn. Consequently, the inshore component of the fishery has been divided into three distinct sub-populations for assessment and stock update purposes: northern (2J and northern 3K), central (southern 3K and northern 3L) and southern (southern 3L). Recruitment has been variable throughout the time-series. Year-class strength increased between 2005 and 2015, but remains much lower than historic levels observed at the peak of fishing activity during the 1980s. The relative strength of all year-classes produced since 1989 has been below the time-series average (DFO 2016). Data gaps and research priorities A degree of uncertainty exists in the catch statistics for northern cod in NAFO Divisions 2J3KL given that there are no quantitative estimates of recreational landings for some years (2006, 2008, ). No formal requirement to report recreational landings is in existence, and as a consequence total catches cannot be fully quantified. A consistent time-series of accurate catch information is needed to quantify total catches and evaluate the impact of fishery removals on stock status. With accurate catch information, additional methods of analysis would be available to examine population dynamics and provide management advice. Fishers have expressed concerns about the lack of data on the current level of consumption of cod by Harp seals (DFO, 2013).More information on predator-prey relationships between populations of northern cod and Harp seals is required to provide a more comprehensive understanding of predation impacts on cod population dynamics. Brattey, J., Cadigan, N.G., Dwyer, K., Healey, B.P., Morgan, M.J., Murphy, E.F., Maddock Parsons, D. and Power, D Assessment of the cod (Gadus morhua) stock in NAFO Divisions 2J+3KL in Canadian Science Advisory Secretariat Science Advisory Report 2010/103. Ottawa, Canada: Department of Fisheries and Oceans (DFO) Canada, 108 pp. DFO Stock assessment of northern (2J3KL) cod in Canadian Science Advisory Secretariat Science Advisory Report 2013/014. Ottawa, Canada: Department of Fisheries and Oceans (DFO) Canada, 27 pp. DFO Stock assessment of northern (2J3KL) in Canadian Science Advisory Secretariat Science Advisory Report 2016/026.

4 Management Details less risk more risk Advised and agreed catches Catch 2015 (t) Advised catch 2015 (t) Agreed TAC 2015 (t) Advised TAC 2016 (t) Monitoring 4,436 None Northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) is assessed annually to estimate biomass in relation to a reference point (B lim ) for long-term sustainability. The stock assessment is based on indices of abundance, biomass, recruitment and total mortality derived from the catch rates of a standardised research trawl survey undertaken in autumn. Estimates of exploitation rates and migration patterns inferred from tagging and hydro-acoustic surveys are also examined. Landings are monitored exhaustively from Canadian log books and sales notes. A degree of uncertainty exists in the catch statistics for northern cod in NAFO Divisions 2J3KL given that quantitative estimates of recreational landings between 2009 and 2013 are not available. There is no formal requirement to report recreational landings, which are believed to represent a substantial component of total removals. Consequently, total catches of northern cod in NAFO Divisions 2J3KL cannot be fully quantified. Control The fisheries for northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) are managed under the Canadian Fisheries Act (1981) through a long-term multi-year management plan that permits an annual catch allowance per licence holder set to achieve stock recovery targets (DFO, 2005). No total allowable catch (TAC) has been set by NAFO since 2006, but commercial fishers have been permitted a fixed annual catch allowance per licence holder. A commercial stewardship fishery for cod and a recreational fishery for groundfish have been permitted since Fishers in the northern cod stewardship fishery have a weekly limit of 2,000 lbs per week from August 15-September 4, 2016 and 3,000 lbs per week for the remainder of the season. Recreational fishers are permitted a maximum catch of 15 fish per boat per day over a 46 day period (DFO 2016b,c). The current assessment indicates that controls have not been entirely effective in increasing spawning stock biomass to above the precautionary limit, and it has remained below B lim since the early 1990s (DFO, 2016). The stock has been subject to a long-term multi-year management plan since the early 1990s, which establishes rules for setting the permitted annual catch allowance per licence holder based on the stock assessment and forecast. There is a single year management plan in place for 2016 (DFO 2016b) Direct control of fishing effort for fleets catching northern cod in NAFO Divisions 2J3KL was introduced in the 1990s, which requires the allocation of effort in kw-days to different groups of vessels, depending on gear, mesh size and area. Northern cod are primarily taken in the targeted commercial stewardship fishery followed by sentinel surveys and as bycatch in mixed fisheries. The commercial stewardship fishery for cod is a limited entry fishery with individual quotas, gear restrictions of six gillnets or longlines of 2000 hooks, seasonal and duration restrictions, and landings are closely monitored at sea and dockside. A minimum mesh size of 5.5 inches (14 cm) has been established in the set gillnet fishery to reduce bycatch and discard rates. A minimum landings size of 41 cm for northern cod is in operation in NAFO Divisions 2J3KL, and discarding has historically mainly comprised of fish below the minimum landings size. No quantitative information is available for discarding by fishery, but qualitative information indicates that widespread discarding occurs in the recreational fishery. The introduction of a moratorium on directed fishing in 1992, historical changes in the set TACs and adherence to the permissible annual catch allowance are likely to have been responsible for an observed increase in discarding of small fish in the recreational fishery. Northern cod are mainly taken as bycatch in the winter flounder fishery, and therefore any management advice for northern cod must also take into account the advice for winter flounder. Surveillance Fisheries on northern cod in NAFO Divisions 2J3KL (Newfoundland and Labrador region) are carried out by a single country (Canada) and surveillance activities to record compliance with national and international fishery control measures are primarily the responsibility of the competent fishery inspection authority in Canada. The requirements for surveillance and sanctions for infringements are laid down in the Northwest Atlantic Fisheries Organisation conservation and enforcement measures legislation. Surveillance activities on fisheries for northern cod in NAFO Divisions 2J3KL include the use of vessel monitoring systems (VMS) onboard all vessels; direct observation by patrol vessels and aerial patrols; inspections of vessels, gear, catches at sea and onshore, verification of logbook data against sales documents. Surveillance activities for fisheries catching northern cod in NAFO Divisions 2J3KL are considered effective. DFO A strategy for the recovery and management of cod stocks in Newfoundland and Labrador. Canada Newfoundland and Labrador action team for cod recovery, November 2005, 69 pp. DFO Stock assessment of northern (2J3KL) cod in Canadian Science Advisory Secretariat Science Advisory Report 2013/14. Ottawa, Canada: Department of Fisheries and Oceans (DFO) Canada, 27 pp. DFO Stock assessment of northern (2J3KL) cod in Canadian Science Advisory Secretariat Science Advisory Report 2016/026. DFO. 2016b. Northern cod Stewardship/by-catch fishery 2J3KL management approach. Fisheries and Oceans Canada. DFO. 2016c Newfoundland and Labrador recreational groundfish fishery. Fisheries and Oceans Canada.

5 Bycatch Details less risk more risk Targeting and behaviour A set longline is a passive form of fishing gear that consists of a mainline and snoods with baited (occasionally unbaited) hooks at regular intervals. Longlines are among the oldest of the traditional passive fishing methods. This method is used throughout the world from small, open inshore boats (i.e. <10 m) to large offshore vessels. In terms of fishing operations, the key difference is that the large, offshore vessels bait and shoot thousands of hooks automatically, whereas the small vessels manually bait and shoot a few hundred hooks each day. Each longline comprises three key elements. At each end of the longline there is a surface marker buoy (or dahn ) with a line leading to an anchor; between the two anchors is the longline itself, the length of which varies with the size of boat and location of fishing. Set at m intervals along the length of the long line are c m snoods to which naturally or artificially baited hooks are attached. The fish are attracted by the bait, hooked and held by the mouth until they are hauled onboard the vessel (Huse et al., 2000). Evidence of bycatch levels in the set longlines fishery for northern cod in NAFO Divisions 2J3KL No quantitative information is available on bycatch levels in the set longline fishery for northern cod in NAFO Divisions 2J3KL. Nevertheless, absolute bycatch across all gears was 1% of catch weight in Northern cod are mainly taken as bycatch in the winter flounder fishery (DFO, 2013). Mitigation measures A moratorium on directed fishing for northern cod in NAFO Divisions 2J3KL has been in place since However, fishers are allowed to catch northern cod in the smallscale commercial stewardship fishery. Measures to reduce the bycatch of non-target species in this fishery include the implementation of a minimum landings size of 41 cm for northern cod and gear restrictions that limit longlines to a maximum of 2000 hooks (DFO, 2005). DFO A strategy for the recovery and management of cod stocks in Newfoundland and Labrador. Canada Newfoundland and Labrador action team for cod recovery, November 2005, 69 pp. DFO Stock assessment of northern (2J3KL) cod in Canadian Science Advisory Secretariat Science Advisory Report 2013/014. Ottawa, Canada: Department of Fisheries and Oceans (DFO) Canada, 27 pp. Huse, I., Løkkeborg, S., and Soldal, A.V Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock. ICES Journal of Marine Science, 57:

6 Habitat Details less risk more risk Longlines have relatively little interaction with the seabed compared to other fishing activities. Nevertheless, longlines can occasionally disturb the seabed. Currents can cause mooring weights/anchors (~30kg) to move over the seabed and lines can get entangled on biogenic features. The distance long lines travel over the seabed during the setting and retrieval phases influences the extent of the habitat impacts. Anchors can be pulled some distance across the seabed before ascending. Mitigation measures A moratorium on directed fishing for northern cod in NAFO Divisions 2J3KL has been in place since However, targeted fishing for northern cod in NAFO Divisions 2J3KL has been spatially restricted to the small-scale commercial stewardship fishery which has a history of exploitation and the use of mobile fishing gears has been prohibited. (DFO, 2013). No additional measures have been established given that the habitat impacts of the set longline fishery are not of major concern to management. DFO A strategy for the recovery and management of cod stocks in Newfoundland and Labrador. Canada Newfoundland and Labrador action team for cod recovery, November 2005, 69 pp. DFO Stock assessment of northern (2J3KL) cod in Canadian Science Advisory Secretariat Science Advisory Report 2013/014. Ottawa, Canada: Department of Fisheries and Oceans (DFO) Canada, 27 pp. All content 2018 Seafish. Origin Way, Europarc, Grimsby, DN37 9TZ. This page created on 21st August 2018 at 05:27am.