COSEWIC Assessment and Status Report on the Atlantic Wolffish Anarhichas lupus in Canada Photo ©Andrew Martinez SPECIAL CONCERN 2012 COSEWIC status reports are working documents used in assigning the status of wildlife species suspected of being at risk. This report may be cited as follows: COSEWIC. 2012. COSEWIC assessment and status report on the Atlantic Wolffish Anarhichas lupus in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. ix + 56 pp. (www.registrelep-sararegistry.gc.ca/default_e.cfm). Previous report(s): COSEWIC. 2000. COSEWIC assessment and status report on the Atlantic wolffish Anarhichas lupus in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 21 pp. (www.sararegistry.gc.ca/status/status_e.cfm). O’Dea, N.R. and R.L. Haedrich. 2000. COSEWIC status report on the Atlantic wolffish Anarhichas lupus in Canada, in COSEWIC assessment and status report on the Atlantic wolffish Anarhichas lupus in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 1-21 pp. Production note: COSEWIC would like to acknowledge Red Méthot for writing the status report on the Atlantic Wolffish, Anarhichas lupus, in Canada, prepared under contract with Environment Canada. The report was overseen and edited by John Reynolds, COSEWIC Marine Fishes Specialist Subcommittee Co-chair. For additional copies contact: COSEWIC Secretariat c/o Canadian Wildlife Service Environment Canada Ottawa, ON K1A 0H3 Tel.: 819-953-3215 Fax: 819-994-3684 E-mail: COSEWIC/[email protected] http://www.cosewic.gc.ca Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur le Loup atlantique (Anarhichas lupus) au Canada. Cover illustration/photo: Atlantic Wolffish — Photo ©Andrew Martinez. Her Majesty the Queen in Right of Canada, 2013. Catalogue No. CW69-14/262-2013E-PDF ISBN 978-1-100-22144-1 Recycled paper COSEWIC Assessment Summary Assessment Summary – November 2012 Common name Atlantic Wolffish Scientific name Anarhichas lupus Status Special Concern Reason for designation This species underwent steep declines in both abundance and area of occupancy over much of its range from the 1980s until the mid-1990s, including its historical stronghold in waters east and north of Newfoundland. Since then it has been increasing in abundance and area of occupancy. While these recent increases are encouraging, the species remains at low abundance compared to the early 1980s. Population increases have probably been aided by reduced commercial fisheries, which take wolffish as bycatch. There have been continuing declines in abundance on the Scotian Shelf and in the Southern Gulf of St. Lawrence, where historically there were fewer individuals than in areas to the east and north. Occurrence Arctic Ocean, Atlantic Ocean Status history Designated Special Concern in November 2000. Status re-examined and confirmed in November 2012. iii COSEWIC Executive Summary Atlantic Wolffish Anarhichas lupus Wildlife Species Description and Significance The Atlantic Wolffish, Anarhichas lupus, is a large-bodied, bottom-dwelling fish with prominent canine-like teeth. It has dark bars on its body that distinguish it from the other wolffish species. This species is taken as bycatch in a wide range of fisheries and was of commercial interest in the 1990s. A very limited commercial fishery persists, with the largest catches reported off Nova Scotia and south of Newfoundland. Distribution The Atlantic Wolffish inhabits northern regions on both sides of the North Atlantic and in the Arctic. In Canadian waters, it is distributed from the Canadian portion of the Gulf of Maine to offshore of Baffin Island, including the Bay of Fundy, Scotian Shelf, Grand Banks off Newfoundland, Gulf of St. Lawrence, northeastern Newfoundland and the Labrador Sea. It is most abundant off northeastern Newfoundland, on the Labrador Shelf and in the southern Grand Banks off Newfoundland. Although there is evidence of genetic differentiation in parts of its range, the information available to date does not support a division of the species into separate designatable units. Habitat The eggs of Atlantic Wolffish are deposited in crevices on rocky bottoms. The larvae are planktonic before becoming established on the bottom. Juveniles and adults are found primarily in the waters of the continental shelf on rocky or sandy bottoms. The fish tolerate a broad temperature range (from -1.5oC to 13oC), although they concentrate in a narrower range and water temperature is thought to be a major factor determining habitat selection. Biology The size at which 50% of females reach sexual maturity is 51.4 cm in the northern part of the range and 68.2 cm in the south. The age at which 50% of the female population reaches sexual maturity is between 8 and 15 years. These population parameters are based on old data as no recent estimates are available. iv Wolffish have internal fertilization. Spawning is thought to occur in the fall and the eggs are guarded by the male until they hatch. Females spawn multiple times over their lifetime and egg production is low. Larvae hatch at a length of over 20 mm and remain near the bottom until the yolk sac is absorbed. Adults can reach up to 152 cm in length. Generation time is estimated to be 15 years for this species. Adults are fairly sedentary but juveniles are capable of wide dispersal. This species feeds primarily on invertebrates and, to a lesser extent, fish. Although juvenile wolffish have been found in the stomachs of seals and carnivorous fish species, larger individuals probably have few predators. Population Sizes and Trends The total number of Atlantic Wolffish in Canadian waters has been estimated at 49 million, including about 5 million mature individuals. There have been declines in both abundance and area occupied over most of its range since the 1970s or 1980s until the mid-1990s. Since then there has been a significant upward trend in abundance and distribution over much of its range, including the waters off the southern Labrador Shelf, which is the historical stronghold of this species. In contrast, adults (but not juveniles) on the Scotian Shelf have continued to decline in abundance and range size. In the Gulf of Maine outside Canadian waters, the Atlantic Wolffish is at the southern limit of its range and is generally rare and unlikely to provide a source of fish that could rescue adjacent Canadian waters. Off western Greenland, its population is estimated at several million and on the Flemish Cap, abundance was estimated at over 10 million in 2006. Threats and Limiting Factors Commercial fishing (directed and bycatch) has been a threat to this species. Recorded catches were relatively high in the 1970s, but declined considerably in the 1990s in Canadian waters due to the closure of several groundfish fisheries. Climate change and its effects on water temperatures may also affect the distribution and abundance of this species. Protection, Status and Ranks The Atlantic Wolffish was first assessed as Special Concern by COSEWIC in November 2000 and was subject to a Management Plan. The status was confirmed in 2012 by COSEWIC. It is also listed as likely to be designated threatened or vulnerable under Quebec’s Act Respecting Threatened or Vulnerable Species (Loi sur les espèces menacées ou vulnérables; R.S.Q., c E-12.01). A petition to list Atlantic Wolffish under the US Endangered Species Act was not accepted. Canada’s small marine protected areas network protects fish in a very small proportion of their range, and some areas are currently subject to a closure to bottom-trawling. v TECHNICAL SUMMARY – CANADIAN RANGE Anarhichas lupus Atlantic (Striped) Wolffish Loup atlantique Range of occurrence in Canada: Eastern Arctic Ocean and the Atlantic Ocean (including the Bay of Fundy, Scotian Shelf, Grand Banks off Newfoundland, Gulf of St. Lawrence, northeastern Newfoundland and the Labrador Sea) Demographic Information Generation time (average age of parents in the population) 15 Is there a continuing decline in the number of mature individuals? No Estimated percent of continuing decline in the total number of mature N/A individuals within 5 years or 2 generations Estimated percent change in the total number of mature individuals over Variable, overall the last 10 years, or 3 generations. declines Strong declines from the 1980s until the mid-1990s over much of the range. Numbers have been increasing in most areas since then, but they remain low compared to the start of the surveys. Projected percent change in the total number of mature individuals over the Unknown next 10 years or 3 generations. Percent reduction or increase in the total number of mature individuals over Unknown any 10 year or 3 generation period, over a time period including both the past and the future. Are the causes of the decline clearly reversible and understood and have Yes they ceased? Are there extreme fluctuations in the number of mature individuals? No Extent and occupancy information Estimated extent of occurrence within Canada’s extent of jurisdiction 1.807 million km² 2.792 million km² (excluding major land masses) Index of area of occupancy (IAO) [Using a 2 × 2 grid] 37,332 km2 Is the total population severely fragmented? No Number of locations∗ Threats include bycatch mortality in diverse fisheries Multiple, but exact over a large region. number unclear Is there a continuing decline in the extent of occurrence? No Is there a continuing decline in the index of area of occupancy? No, increases