COSEWIC Assessment and Update Status Report on the Ivory Gull Pagophila eburnea in Canada ENDANGERED 2006 COSEWIC COSEPAC COMMITTEE ON THE STATUS OF COMITÉ SUR LA SITUATION ENDANGERED WILDLIFE DES 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: COSEWIC 2006. COSEWIC assessment and update status report on the Ivory Gull Pagophila eburnea in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 42 pp. (www.sararegistry.gc.ca/status/status_e.cfm). Previous reports: COSEWIC 2001. COSEWIC assessment and update status report on the Ivory Gull Pagophila eburnea in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. iv + 10 pp. (www.sararegistry.gc.ca/status/status_e.cfm) Alvo, Robert and S.D. Macdonald. 1996. Updated COSEWIC status report on the Ivory Gull Pagophila eburnea in Canada. Committee on the Status of Endangered Wildlife in Canada. 1-10 pp. MacDonald, S.D. 1979. COSEWIC status report on the Ivory Gull Pagophila eburnea in Canada. Committee on the Status of Endangered Wildlife in Canada. 1-25 pp. Production note: COSEWIC would like to acknowledge Iain J. Stenhouse, Grant Gilchrist, Mark L. Mallory and Gregory J. Robertson for writing the update status report on the Ivory Gull Pagophila eburnea in Canada. COSEWIC also gratefully acknowledges the financial support of the Canadian Wildlife Service, Environment Canada for the preparation of this report. The COSEWIC report review was overseen by Richard Cannings, Co-chair, COSEWIC Birds Species Specialist Subcommittee, with input from members of COSEWIC. That review may have resulted in changes and additions to the initial version of the report. 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 Également disponible en français sous le titre Évaluation et Rapport de situation du COSEPAC sur la mouette blanche (Pagophila eburnea) au Canada – Mise à jour. Cover illustration: Ivory Gull – Photograph provided by Grant Gilchrist, Environment Canada. ©Her Majesty the Queen in Right of Canada 2006 Catalogue No. CW69-14/13-2006E-PDF ISBN 0-662-43267-3 Recycled paper COSEWIC Assessment Summary Assessment Summary – April 2006 Common name Ivory Gull Scientific name Pagophila eburnea Status Endangered Reason for designation Aboriginal Traditional Knowledge and intensive breeding colony surveys over the last four years indicate that the Canadian breeding population of this long-lived seabird has declined by 80% over the last 20 years. This bird feeds along ice-edge habitats in the high Arctic and breeds in very remote locations. Threats include contaminants in food chain, continued hunting in Greenland, possible disturbance by mineral exploration at some breeding locations, and degradation of ice-related foraging habitats as a result of climate change. Occurrence Northwest Territotries, Nunavut, Newfoundland-Labrador. Status history Designated Special Concern in April 1979. Status re-examined and confirmed in April 1996 and in November 2001. Status re-examined and designated Endangered in April 2006. Last assessment based on an update status report. iii COSEWIC Executive Summary Ivory Gull Pagophila eburnea Species information The Ivory Gull is a medium-sized gull, approximately 10% larger and longer- winged than the Black-legged Kittiwake (Rissa tridactyla). It is distinctive at all ages, but is particularly striking in its pure white adult plumage. Recent phylogenetic analysis based on mitochondrial DNA has provided strong evidence that the Ivory Gull is a sister taxon to the Sabine’s Gull (Xema sabini). Distribution The Ivory Gull has a circumpolar, but patchy, breeding distribution across the high arctic. Small, scattered colonies occur in Arctic Canada, Greenland, Spitzbergen, and the northern islands and archipelagoes of Russia in the Kara Sea. The wintering distribution of the Ivory Gull is poorly known but is generally along the southern edge of pack ice. In Canada, the Ivory Gull has a highly restricted range while breeding, nesting exclusively in Nunavut Territory. Habitat Ivory Gulls require breeding sites that are safe from terrestrial predators, particularly the arctic fox. They nest in near marine waters that are partially free of ice in late May and early June; colonies are found concentrated around Jones and Lancaster Sounds, with colonies occurring on southeastern Ellesmere Island, eastern Devon Island, and the Brodeur Peninsula of northern Baffin Island. Biology Ivory Gulls are thought to first breed after their second year. They usually lay 1-2 eggs. Population sizes and trends Until recently, the Canadian Arctic was thought to support 20-30% of the entire global breeding population and to contain colonies of global importance. However, iv aerial surveys conducted during the first two weeks of July in 2002, 2003, 2004, and 2005 suggest that the Canadian breeding population has declined. During those years, 31 colony locations were resurveyed where colonies had previously occurred in the 1970s and 1980s. Although recent surveys were conducted at an ideal time of year, under clear weather conditions and using identical methods to previous historical surveys, only 9 of these colonies showed signs of activity in recent surveys. Further, the number of gulls detected at colonies on Ellesmere, Devon, Cornwallis, Seymour, and Baffin Islands totalled 88, 319, 305, and 210 in 2002, 2003, 2004, and 2005 respectively despite the broadest geographic search effort ever for this species in Canada. These values represent an apparent population decline of approximately 80% since the 1980s. At-sea surveys provide further evidence for decline; in the High Arctic in August, four times as many Ivory Gulls were seen in 1993 than in 2002. Long-term Inuit residents of four communities in Arctic Canada also report dramatic declines in the number of Ivory Gulls observed at communities and during spring and fall migration along ice edges. There is also evidence from seal hunters that there are fewer Ivory Gulls wintering in the Labrador Sea compared with the late 1970s. Limiting factors and threats Although Ivory Gulls winter in association with pack ice in the north Pacific and Atlantic oceans, and nest in extremely remote breeding locations, there are now several confirmed threats to Ivory Gulls in Canada and globally. These include illegal shooting of adults for food (particularly in west Greenland during spring and fall migration), climate change that is altering ice conditions in the circumpolar Arctic, oiling at sea, and escalating diamond exploration and drilling activities on the Brodeur Peninsula of Baffin Island (one of the key breeding locations of the species in Canada). In addition, toxic pollutants that bioaccumulate at high trophic levels are known to occur among Ivory Gulls breeding in Canada. Existing protection The Ivory Gull is protected in North America under the Migratory Birds Convention Act (1994) and Migratory Bird Regulations. It has also been protected in West Greenland since 1977 under the Local Government Order of 21st December on bird hunting in West Greenland. In 1988, hunting regulations were revised and applied to all of Greenland, under the Greenland Home Rule order of 5 May 1988 on protection of birds in Greenland. However, band returns from Ivory Gulls ringed in Arctic Canada suggest that illegal harvest continues. The Ivory Gull is on the Norwegian Red List, in the category ‘declining, monitoring’ (DM). In Svalbard, it has been protected since 1978, under the Svalbard Environmental Protection Act. In Russia, it is registered as a Category 3 (Rare) species in the Red Data Book of the former USSR. v COSEWIC HISTORY 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. On June 5th 2003, the Species at Risk Act (SARA) was proclaimed. SARA establishes COSEWIC as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process. COSEWIC MANDATE The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. Designations are made on native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fishes, arthropods, molluscs, vascular plants, mosses, and lichens. COSEWIC MEMBERSHIP COSEWIC comprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non-government science members and the co-chairs of the species specialist subcommittees and the Aboriginal Traditional Knowledge subcommittee. The Committee meets to consider status