Atlantic Wolffish Anarhichas Lupus

Atlantic Wolffish Anarhichas Lupus

COSEWIC Assessment and Status Report on the Atlantic Wolffish Anarhichas lupus in Canada SPECIAL CONCERN 2000 COSEWIC COSEPAC COMMITTEE ON THE STATUS OF COMITÉ SUR LA SITUATION DES ENDANGERED WILDLIFE IN ESPÈCES EN PÉRIL CANADA AU CANADA 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: Please note: Persons wishing to cite data in the report should refer to the report (and cite the author(s)); persons wishing to cite the COSEWIC status will refer to the assessment (and cite COSEWIC). A production note will be provided if additional information on the status report history is required. 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. For additional copies contact: COSEWIC Secretariat c/o Canadian Wildlife Service Environment Canada Ottawa, ON K1A 0H3 Tel.: (819) 997-4991 / (819) 953-3215 Fax: (819) 994-3684 E-mail: COSEWIC/[email protected] http://www.cosewic.gc.ca Ếgalement disponible en français sous le titre Évaluation et Rapport de situation du COSEPAC sur le loup atlantique (Anarhichas lupus) au Canada Cover illustration: Atlantic wolffish — fom Scott and Scott, 1988. Her Majesty the Queen in Right of Canada 2004 Catalogue No. CW69-14/262-2003E-IN ISBN 0-662-33622-4 Recycled paper COSEWIC Assessment Summary Assessment Summary – November 2000 Common name Atlantic wolffish Scientific name Anarhichas lupus Status Special Concern Reason for designation The total population of this large, solitary, slow-growing, late-maturing, nest-building benthic fish has declined significantly since the 1970s. Apparent threats are related to fishing and habitat alteration, perhaps compounded by environmental change. Occurrence Atlantic Ocean Status history Designated Special Concern in November 2000. Assessment based on a new status report. iii COSEWIC Executive Summary Atlantic Wolffish Anarhichas lupus Description Wolffish are characterized by the prominent, canine-like teeth in the front of the jaws, the elongate body, and the lack of pelvic fins. The Atlantic wolffish, Anarhichas lupus, is a large, bottom-dwelling predatory fish and is distinguished from the other two Atlantic species by the dark transverse bars on the body, the firm musculature, and the arrangement of the teeth on the roof of the mouth. Distribution The Atlantic wolffish occurs in continental shelf waters across the North Atlantic from northern France to Cape Cod. In the western North Atlantic, its greatest abundance occurs off northeast Newfoundland. Habitat The Atlantic wolffish lives among boulder fields on rocky or hard clay bottoms of the continental shelf. It can be found as deep as 500 m in cold to cool ocean waters. General Biology Spawning occurs late in the year. The large eggs are deposited in a large mass on the sea bottom, and are guarded by the male until they hatch. The young remain mostly associated with the bottom and do not disperse very far. The adults appear only to make limited seasonal migrations from deep to shallower water. Growth rates are slow. Apparently different temperature and depth preferences, and different spawning times, suggest that discrete regional populations may be the rule. Wolffish feed primarily on hard-shelled benthic invertebrates such as echinoderms, molluscs and crustaceans. Population Size and Trends Scientific surveys from most parts of the western Atlantic range indicate declines in abundance over the past 20 years. Since 1978, catch rates in Newfoundland waters are down by 91% over two wolffish generations, and for all Canadian waters numbers iv are down by 87%. Mean size has also declined over time, and is now smaller than the size at maturity off Newfoundland. Numbers have declined steadily, the number of locations where the species occurs has declined, and the range where the species is abundant may be shrinking. Slow growth, a nesting habit, and limited dispersal make rescue unlikely. Nearby extra-territorial populations are experiencing the same difficulties as Canadian ones. Bottom trawling and dredging have probably damaged habitat. Future monitoring will be difficult. Limiting Factors and Threats Atlantic wolffish figure in commercial landings, at one time as a target species but now only as by-catch. Canada and Greenland have been the major countries involved since 1980, and Portugal was important in the 1990s. Landings in the western Atlantic peaked in 1979 at around 22,000 tonnes but fell steadily to under 2,000 by 1996. Even removals as by-catch have a negative impact on wolffish populations, and bottom trawling which destroys and disrupts habitat is probably detrimental as well. Existing Protection Because the Atlantic wolffish is not at present the target of a directed fishery in the western Atlantic, it is unmanaged and there are no specific mechanisms, such as total allowable catch limits, in place that afford it protection. v COSEWIC MANDATE The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) determines the national status of wild species, subspecies, varieties, and nationally significant populations that are considered to be at risk in Canada. Designations are made on all native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fish, lepidopterans, molluscs, vascular plants, lichens, and mosses. COSEWIC MEMBERSHIP COSEWIC comprises representatives from each provincial and territorial government wildlife agency, four federal agencies (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biosystematic Partnership), three nonjurisdictional members and the co-chairs of the species specialist groups. The committee meets to consider status reports on candidate species. DEFINITIONS Species Any indigenous species, subspecies, variety, or geographically defined population of wild fauna and flora. Extinct (X) A species that no longer exists. Extirpated (XT) A species no longer existing in the wild in Canada, but occurring elsewhere. Endangered (E) A species facing imminent extirpation or extinction. Threatened (T) A species likely to become endangered if limiting factors are not reversed. Special Concern (SC)* A species of special concern because of characteristics that make it particularly sensitive to human activities or natural events. Not at Risk (NAR)** A species that has been evaluated and found to be not at risk. Data Deficient (DD)*** A species for which there is insufficient scientific information to support status designation. * Formerly described as “Vulnerable” from 1990 to 1999, or “Rare” prior to 1990. ** Formerly described as “Not In Any Category”, or “No Designation Required.” *** Formerly described as “Indeterminate” from 1994 to 1999 or “ISIBD” (insufficient scientific information on which to base a designation) prior to 1994. The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) was created in 1977 as a result of a recommendation at the Federal-Provincial Wildlife Conference held in 1976. It arose from the need for a single, official, scientifically sound, national listing of wildlife species at risk. In 1978, COSEWIC designated its first species and produced its first list of Canadian species at risk. Species designated at meetings of the full committee are added to the list. Environment Environnement Canada Canada Canada Canadian Wildlife Service canadien Service de la faune The Canadian Wildlife Service, Environment Canada, provides full administrative and financial support to the COSEWIC Secretariat. vi COSEWIC Status Report on the Atlantic Wolffish Anarhichas lupus in Canada Niall R. O’Dea1 Richard Haedrich1 2000 1 Memorial University of Newfoundland Department of Biology 4 Clarke Place St. John’s, NL A1C 5S7 TABLE OF CONTENTS SPECIES INFORMATION............................................................................................... 3 Name and Classification .............................................................................................. 3 Description................................................................................................................... 3 DISTRIBUTION............................................................................................................... 4 Global Range............................................................................................................... 4 Canadian Range.......................................................................................................... 4 HABITAT .........................................................................................................................4 Definition......................................................................................................................4 Trends ......................................................................................................................... 6 GENERAL BIOLOGY...................................................................................................... 7 Reproduction ..............................................................................................................

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