Northern Goshawk Laingi Subspecies
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COSEWIC Assessment and Update Status Report on the Northern Goshawk Laingi subspecies Accipiter gentilis laingi in Canada THREATENED 2000 COSEWIC COSEPAC COMMITTEE ON THE STATUS OF COMITÉ SUR LA SITUATION DES ENDANGERED WILDLIFE ESPÈCES EN PÉRIL IN 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 update status report on the Northern Goshawk Laingi subspecies Accipiter gentilis laingi in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 36 pp. (www.sararegistry.gc.ca/status/status_e.cfm) Cooper, J.M. and P.A. Chytyk. 2000. Update COSEWIC status report on the Northern Goshawk Laingi subspecies Accipiter gentilis laingi in Canada, in COSEWIC assessment and update status status report on the Northern Goshawk Laingi subspecies Accipiter gentilis laingi in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 1-36 pp. Previous Report Duncan P. and D.A. Kirk. 1995. COSEWIC status report on the Queen Charlotte Goshawk Accipiter gentilis laingi in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 44 pp. Production note: The Northern Goshawk laingi subspecies Accipiter gentilis laingi was formerly designated by COSEWIC as the Queen Charlotte Goshawk Accipiter gentilis laingi. Throughout the status report the species is referred to as the Queen Charlotte Goshawk which is a subspecies of the Northern Goshawk. 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 Rapport du COSEPAC sur la situation de l’Autour des palombes de la sous-espèce laingi (Accipiter gentilis laingi) au Canada – Mise à jour. Cover illustration: Northern Goshawk laingi subspecies — illustration by Judy Shore, Richmond Hill, Ontario. ©Minister of Public Works and Government Services Canada 2004 Catalogue No. CW69-14/12-2002E-IN ISBN 0-662-32941-4 Recycled paper COSEWIC Assessment Summary Assessment Summary – November 2000 Common name Northern Goshawk laingi subspecies Scientific name Accipiter gentilis laingi Status Threatened Reason for designation This small, sedentary goshawk population has been negatively impacted by degradation of forested habitat. Occurrence British Columbia Status history Designated Special Concern in April 1995. Status re-examined and designated Threatened in November 2000. Last assessment based on an update status report. iii COSEWIC Executive Summary Northern Goshawk Laingi subspecies Accipiter gentilis laingi The Northern Goshawk laingi subspecies (Accipiter gentilis laingi) is a subspecies of the Northern Goshawk (A. gentilis) that occurs only on the Pacific coast of North America. It is resident from southeastern Alaska through coastal British Columbia, and probably south to the Olympic Peninsula of Washington. Throughout the status report the species is referred to as the Queen Charlotte Goshawk which is a subspecies of the Northern Goshawk. Populations and range of the Queen Charlotte Goshawk are relatively very small compared to those for Northern Goshawk, which occurs over much of northern North America. In British Columbia, populations of the Queen Charlotte Goshawk are likely restricted to Vancouver Island, the Queen Charlotte Islands, and other large coastal islands. The status of Northern Goshawks on the coastal mainland remains uncertain, however, recent studies suggest that some Queen Charlotte Goshawks could occur there. Habitat modeling suggests that most of the global population of the Queen Charlotte Goshawk occurs in British Columbia. Recent surveys on Vancouver Island and Queen Charlotte Islands suggested most of the provincial population occurs on Vancouver Island. We estimate about 300 breeding pairs on Vancouver Island and 50 breeding pairs on the Queen Charlotte Islands, but lack of surveys or habitat assessments in many areas make these estimates very uncertain. Significant threats to habitat include continued logging of preferred, low elevation, old-growth coniferous forest and suitable mature second-growth forest. Habitat modeling suggests that populations have declined from historical numbers because habitat has been significantly degraded. We predict that declines will continue as old- growth forests continue to be logged and harvest rotations shorten for second-growth forests, resulting in some permanent loss of suitable Queen Charlotte Goshawk habitat in large parts of managed forests. iv 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. v Update COSEWIC Status Report on the Northern Goshawk Laingi subspecies Accipiter gentilis laingi in Canada John M. Cooper1 Paul A. Chytyk2 2000 1 Manning, Cooper and Associates Environmental Consultants Box 20157 4-0769 Fifth Street Sidney, BC V8L 5C9 TABLE OF CONTENTS SPECIES INFORMATION............................................................................................... 4 Description and Taxonomy .......................................................................................... 4 DISTRIBUTION............................................................................................................... 4 Global ..........................................................................................................................4 North America.............................................................................................................. 4 Canada ........................................................................................................................ 5 HABITAT .........................................................................................................................6 General........................................................................................................................ 6 Nesting Habitat ............................................................................................................ 6 Foraging Habitat .......................................................................................................... 8 Trends in Habitat Quality ............................................................................................. 9 Protection/Ownership of Habitat ................................................................................ 10 GENERAL BIOLOGY.................................................................................................... 12 Reproduction