Atlantic wolffish (Anarhichas lupus) COSEWIC assessment and status report 2012
Official title: COSEWIC Assessment and Status Report on the Atlantic Wolffish Anarhichas lupus in Canada - 2012
Special Concern
2012
Table of Contents
- COSEWIC Assessment Summary
- COSEWIC Executive Summary
- Technical Summary – Canadian Range
- Preface
- Wildlife Species Description and Significance
- Distribution
- Habitat
- Biology
- Population Sizes and Trends
- Threats and Limiting Factors
- Protection, Status and Ranks
- Acknowledgements and Authorities Consulted
- Information Sources
- Biographical Summary of Report Writer
List of Figures
- Figure 1. Atlantic Wolffish (Anarhichas lupus) and distinguishing morphological features. Photo credit: C. Nozères, Department of Fisheries and Oceans.
- Figure 2. Potential global range of the Atlantic Wolffish. Source: Kaschner et al. (2008).
- Figure 3. Map of geographic locations mentioned in this document.
- Figure 4. Northwest Atlantic Fisheries Organization (NAFO) Convention Areas.
- Figure 5. Extent of occurrence in Canada of Atlantic Wolffish based on Department of Fisheries and Oceans Canada research trawl survey catches.
- Figure 6. Index of area of occupancy in Canada of Atlantic Wolffish based on Department of Fisheries and Oceans Canada research trawl survey catches.
- Figure 7. Index of area of occupancy (DWAO) of the Atlantic Wolffish for the Newfoundland Grand Banks (3LNO) and the Labrador Sea (2J3K) based on Newfoundland spring and fall research trawl surveys. The vertical lines indicate a fishing gear change (blue line for the spring, black for fall). During fall, only Division 3L was surveyed prior to 1990. From Simpson et al. (2011).
- Figure 8. Index of area of occupancy (DWAO) of Atlantic Wolffish for the Scotian Shelf (NAFO Divisions 4VWX), Southern Newfoundland (3Ps), and the Southern Gulf (4T). The vertical lines indicate a fishing gear change. From Simon et al. (2011).
- Figure 9. Index of area of occupancy (DWAO) of Atlantic Wolffish for the Gulf of St Lawrence (NAFO Division 4RST). From Bourdage and Ouellet (in prep.).
- Figure 10. Winter Arctic Oscillation (AO) and North Atlantic Oscillation (NAO) indices with 1950-2000 as base period. Data are for the Jan-Mar winter period. Source: Yashayaev and Greenan (2011).
- Figure 11. Length frequency of Atlantic Wolffish based on raw catch data from the Newfoundland and Labrador fall research trawl surveys from 1981 to 1994 and 1995 to 2010. Individuals > 51 cm were considered mature. Source: Data provided by Mark Simpson, pers. comm. 2010 and 2012.
- Figure 12. Atlantic Wolffish abundance estimates (± CI) from Newfoundland and Labrador fall research trawl surveys for the Grand Banks (3LNO) and southern Labrador Shelf (2J3KL). The dotted vertical line indicates a fishing gear change.
- Figure 13. Atlantic Wolffish abundance (total and mature fish > 51 cm) based on Newfoundland and Labrador fall research trawl surveys for the southern Labrador Shelf (NAFO Divisions 2J3KL) from 1981 to 2009. The vertical line indicates a fishing gear change.
- Figure 14. Natural log of Atlantic Wolffish abundance estimates from Newfoundland fall research trawl surveys for the southern Labrador Shelf (NAFO Divisions 2J3KL). Fitted regressions are shown. The vertical line indicates a gear change.
- Figure 15. Atlantic Wolffish abundance estimates (± 1 CI) for the Grand Banks (NAFO Division 3LNO) based on Newfoundland spring research trawl surveys. Vertical lines indicate a fishing gear change. The “total” line indicates the sum of the abundances for all divisions only when all divisions were surveyed. Source: Raw data provided by Mark Simpson, pers. comm., 2010.
- Figure 16. Natural log of Atlantic Wolffish abundance estimates for the Grand Banks (NAFO Division 3LNO) based on Newfoundland spring research trawl surveys. Fitted regressions are shown. The vertical lines indicate fishing gear changes.
- Figure 17. Mature and total Atlantic Wolffish abundances (± CI) estimated from the Maritimes summer research trawl survey on the Scotian Shelf and part of the Gulf of Maine (NAFO Divisions 4VWX) and of Southern Newfoundland (NAFO Division 3Ps). Sources: 4VWX from Simon et al. (2011), 3Ps from Simpson et al. (2011).
- Figure 18. Natural log of Atlantic Wolffish abundance estimates for the Scotian Shelf (NAFO Division 4VWX) based on Maritimes research trawl surveys. Fitted regressions are shown. The vertical line indicates a fishing gear change.
- Figure 19. Length frequency of Atlantic Wolffish from the Scotian Shelf Maritimes summer research trawl survey (based on total stratified random sampling abundance estimates). See text for caveats about gear changes.
- Figure 20. Natural log of Atlantic Wolffish abundance estimates for southern Newfoundland (NAFO Division 3Ps) based on Newfoundland spring research trawl surveys. Fitted regressions are shown. The breaks are due to fishing gear changes.
- Figure 21. Total Atlantic Wolffish abundance (± 1 CI) for the Southern Gulf (NAFO Division 4T). The vertical line indicates a fishing gear change. There were too few adults to allow them to be depicted separately (Table 6). Source: Benoit, H. pers. comm. (2012).
- Figure 22. Natural log of Atlantic Wolffish abundance estimates from Southern Gulf research trawl surveys for NAFO Division 4T. Fitted regressions are shown. The vertical line indicates a fishing gear change. There were too few adults to allow them to be depicted separately (Table 6).
- Figure 23. Atlantic Wolffish abundance estimates (± 1 CI) from summer research trawl surveys for the Gulf of St. Lawrence (NAFO Division 4RST). The abundance of mature fish is based on the proportion of fish > 51 cm.
- Figure 24. Natural log of Atlantic Wolffish abundance estimates from summer research trawl surveys for the Gulf of St. Lawrence (NAFO Division 4RST). Fitted regressions are shown.
- Figure 25. Atlantic Wolffish abundance indices based on two surveys conducted west of Greenland. Coverage of the Danish survey (Nygaard and Jørgensen 2010) varied over time. The German survey (Fock and Stransky 2009) covered NAFO Divisions 1C to 1F. The two surveys followed different protocols and used different gear.
- Figure 26. Atlantic Wolffish abundance estimates from surveys on the Flemish Cap (NAFO Division 3M). Source: González-Troncoso and Paz (2007).
- Figure 27. Reported wolffish (unspecified species) landings in NAFO divisions located partly or entirely in Canadian waters. Source: NAFO (2010).
List of Tables
- Table 1. Atlantic Wolffish sample details for microsatellite analysis in McCusker and Bentzen (2010b).
- Table 2. Atlantic Wolffish Fst microsatellite analysis in McCusker and Bentzen (2010b). Location names correspond to Table 1.
- Table 3. Information sources used to determine the distribution of the Atlantic Wolffish in Canadian waters
- Table 4. Research surveys used in this report to determine Atlantic Wolffish abundance trends.
- Table 5. DFO-NL research trawl surveys were conducted in spring on the Grand Banks (Div. 3LNOPs; refer to Fig. 4 and Fall/Winter on the Labrador Shelf to Grand Banks (Div. 2GHJ3KLNO). Dark boxes indicate a survey was undertaken.
- Table 6. Current minimum trawlable abundance estimates of Atlantic Wolffish (total and mature populations) in each NAFO Division based on DFO research trawl surveys. Values are not comparable between surveys due to different catchability of the different gears used. Individuals > 51 cm total length are considered mature, except those from the Maritimes summer survey (> 67 cm).
- Table 7. Atlantic Wolffish abundance indices for the Grand Banks and southern Labrador Shelf based on Newfoundland & Labrador fall research trawl survey data. (Totals for 3LNO are presented for the spring survey in Table 9.)
- Table 8. Trends in Atlantic Wolffish abundance indices based on research trawl survey data.
- Table 9. Atlantic Wolffish abundance indices for the Grand Banks based on Newfoundland spring research trawl survey data.
- Table 10. Atlantic Wolffish abundance indices from the Scotian Shelf, Southern Gulf, and Southern Newfoundland based on the Maritime summer research trawl survey data (Div. 4VWX and Subdivision 5Y), or Newfoundland spring research trawl survey data (Subdivision 3Ps) and Southern Gulf research trawl survey (Div. 4T) and the Northern Gulf summer research trawl survey data (Division 4RST).
Page details
- Date modified: