Cackling Goose, Aleutian Branta hutchinsii leucopareia

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1 Cackling Goose, Aleutian Branta hutchinsii leucopareia Conservation Status Heritage Agency G Rank: G3 USFWS/NOAA: Delisted S Rank: S3B SOA: Species of Greatest Conservation Need BLM: USFS: Class: Aves Order: Anseriformes AA: IUCN: Final Rank Conservation category: VIII. Yellow VIII = low status and either high biological vulnerability or high action need Category Range Status: -0 to 0 4 Biological: -50 to Action: -40 to 40-3 Higher numerical scores denote greater concern Status Population Trend ( to 10) Historical declines due to fox introductions in from the 1700s to the 1930s (Jones 1963). The population breeding in the western Aleutian Islands grew modestly from about 800 geese in 1975, increasing at about 15% per year through Between 199 and 003, direct spring counts increased at an average of 0% per year; indirect estimates increased at an average of 3% from 1996 to 003. Breeding ground surveys and winter counts indicate little increase in geese from the central Aleutian Islands and Semidi Islands (USFWS 001a). Current population trend for Aleutian Canada Geese is upward, averaging about 0% annual growth since 1990, when reclassified from endangered to threatened (USFWS 1990, 001a). Population estimates from 1973 to 006 demonstrate an increasing population size (Trost, personal communication). Distribution Trend ( to 10) This species used to nest from Kodiak Island to Kuril Islands in Russia. Currently restricted to 10 fox free islands in the Aleutians (Byrd 1998). Prior to recovery, only known to occur on Buldir Island. Fox were removed from its former nesting habitat and the species has recovered on 10 islands (USFWS 1999). Area occupied declined by >50%. Biological - variables measure the trend in a taxon s population status or distribution. Higher status scores denote taxa with known declining trends. Status scores range from -0 (increasing) to 0 (decreasing). Population Size ( to 10) Status Total: - variables measure aspects of a taxon s distribution, abundance and life history. Higher biological scores suggest greater vulnerability to extirpation. Biological scores range from -50 (least vulnerable) to 50 (most vulnerable). >30,000 (Gibson and Byrd 007). Based on mark resight population estimates in California the total population in 011 was estimated at 111,800 (95% CI =91,800, 131,800; USFWS 011). Latest census conducted on Buldir Island estimated number of breeding geese at 7,000 individuals, and total population at 17,500 birds (Byrd 1995). In 1995 an estimated 700 birds nested on Agattu Island, where Aleutian geese were reintroduced between the late 1970s and mid-1980s (Byrd 1995). In 003, nesting pairs numbered in the low thousands with room for expansion, giving Agattu Island the potential to become the largest breeding site (Byrd and Williams 003). The 1995 estimate of breeding geese on Nizki-Alaid Islands was 48 (or 60 total geese); Byrd (1995) states that the number of geese breeding at Nizki Island could approach 500 in the future. Elsewhere in the Aleutians, 10 birds nested in the Rat Islands in 1995 (Byrd 1995), and about 50 birds have nested at Chagulak Island between 1990 and 00 (Byrd 1990, Byrd and Williams 00b). Buldir Island population comprises 80% of Alaska population, thus ~9000 to adults in Alaska. Total estimates from direct spring counts indicated about 6,800 birds in 4 1

2 winter of 00, and from indirect estimation over 5,700 birds in spring of 003 (Drut and Trost 003). Total population on Buldir Island 17,500 birds (Byrd 1995). Range Size ( to 10) Present breeding range includes 10 islands along Aleutian Archipelago. Largest remnant breeding populations on Buldir Island (Jones 1963, Byrd 1998); small remnant population on Chagulak Island (Bailey and Trapp 1984); in the Semidi Islands, a small remnant population remains on Kiliktagik Island (Hatch and Hatch 1983) and geese have recently begun nesting on Anowik Island (Beyersdorf and Pfaff 1995). In the Near Island group, relocation programs established additional breeding populations on Agattu and Alaid-Nizki Islands (Byrd 1998). Recent breeding documentation on Amchitka Island, Amukta Island and Little Kiska Island (Rat Island group), but current status unknown (U.S. Fish and Wildlife Service 001). In 1994 and 1995, geese translocated from Buldir Island were released on Skagul and Yunaska Islands (Williams 1995, Williams et al. 1995). Females from both of these islands (13 from Skagul and 15 from Yunaska) were observed on wintering grounds in California in , suggesting birds may be persisting on these islands and perhaps forming additional breeding populations, although further surveys have not been conducted to support this hypothesis (USFWS 001a). Precise spring and fall migration routes through Alaska are not known (U.S. Fish and Wildlife Service 1991). Some birds are thought to migrate along the Aleutian chain at least as far east as Unimak Island on their fall migration southward (Woolington et al. 1979). Range size ~616km. Population Concentration ( to 10) Occurs on 10 islands in the Aleutian and Semidi Islands. Reproductive Potential Age of First Reproduction (-5 to 5) Most do not breed until years of age (Mowbray et al. 00). Number of Young (-5 to 5) Single clutch of 1 to 9 eggs with mean ranging from 4 to 5.6 (Cooper 1978, Moser and Rusch 1989, Mowbray et al. 00). Ecological Specialization Dietary (-5 to 5) Eats various marsh plants, algae, sedge and grass seeds, grain (especially in winter), berries, insects and other terrestrial insects, crustaceans, and mollusks. Obtains food items from water surface or beneath surface in shallow water; also gleans from ground surface (Ehrlich et al. 199). Habitat (-5 to 5) Aleutian Cackling geese breed exclusively on a small number of Aleutian Islands (U.S. Fish and Wildlife Service 1991). Nesting areas are located on grassy hillsides, along streams, in marshes and lagoons, and on rugged sea cliffs cut by watercourses where grasses and sedges grow in profusion (Murie 1959, Jones 1963, U.S. Fish and Wildlife Service 1980). Molting habitat is generally located in the uplands. Night roosting areas include shallow pools and ponds on the islands. During migration and on wintering grounds, the geese are commonly found in marshes, pastures and grass crops, harvested agriculture fields and flood-irrigated and non-irrigated land (U.S. Fish and Wildlife Service 1980, 1991). Biological Total: Action - variables measure current state of knowledge or extent of conservation efforts directed toward a given taxon. Higher action scores denote greater information needs due of lack of knowledge or conservation action. Action scores range from -40 (lower needs) to 40 (greater needs). Management Needs ( to 10) Designated as an endangered species in 1967; downlisted to threatened in 1990; delisted in 001 (U.S Fish and Wildlife Service 001a). All known breeding locations are protected within the Alaska Maritime National Wildlife Refuge. Currently managed and protected under the Migratory Bird Treaty Act (MBTA 1918). The U.S. Fish and Wildlife Service will continue to monitor the Aleutian Canada Goose for five years if the population declines below the recovery threshold, the species may be re-listed. Subsistence harvest is allowed except hunting on Semidi Islands and egg gathering anywhere (USFWS 006c). Active removal of fox on islands with this species began in The service had plans to remove foxes from 1 additional islands between 1998 and 004. Restoration of Attu Island was planned for Translocations to fox free islands has occurred and there were plans to release birds on Attu Island (Pacific Flyway Council 1999). Monitoring Needs ( to 10) Several types of surveys, as well as banding and marking, provide reasonably good information on the abundance of Aleutian -

3 geese. Continued work is needed to improve the frequency and coverage of surveys to document nesting distribution in the Aleutian Islands. U. S. Fish and Wildlife Service approved a 5 year post-delisting monitoring program that includes surveys of all sites where restoration has occurred (Byrd and Williams 004). Research Needs ( to 10) The decline of the Aleutian Canada goose was primarily the result of the introduction of Arctic foxes (Alopex lagopus) and, to a lesser extent, red foxes (Vulpes vulpes) to its breeding islands for the purpose of developing a fur industry. Between 1750 and 1936, Arctic and red foxes were introduced to more than 190 islands within the breeding range of the Aleutian Canada goose in Alaska. Foxes remain on many of the islands and are a significant obstacle to the full recovery of the geese across their former range (Bailey 1993). Nesting geese are susceptible also to Norwegian rats (Rattus norvigicus) introduced before or during World War II, and predation by Bald Eagles (Haliaeetus leucocephalus) may be an important factor in limiting reestablishment of geese on fox-free islands (Byrd 1998). Active removal of fox on islands with this species began in The service had plans to remove foxes from 1 additional islands between 1998 and 004. Restoration of Attu Island was planned for Translocations to fox free islands has occurred and there were plans to release birds on Attu Island (Pacific Flyway Council 1999). Survey Needs ( to 10) The 1991 Aleutian Canada Goose Recovery Plan (U.S. Fish and Wildlife Service 1991) outlines the primary research needs necessary for meeting the recovery objectives. These include: 1. Determine habitat characteristics for breeding use areas in the central Aleutians and Semidi Islands and 6. Determine more precisely, the migration routes and wintering areas for the different breeding segments of Aleutian geese. Several types of surveys, as well as banding and marking, provide reasonably good information on distribution. Continued work is needed to improve the frequency and coverage of surveys to document nesting distribution in the Aleutian Islands. U. S. Fish and Wildlife Service approved a 5 year post-delisting monitoring program that includes surveys of all sites where restoration has occurred (Byrd and Williams 004). Action Total: -3 Supplemental Information Harvest: Seasonal Occurrence: Taxonomic Significance: Range Map - variables do not receive numerical scores. Instead, they that are used to sort taxa to answer specific biological or managerial questions. Not substantial Breeding Subspecies % Global Range in Alaska: >10% % Global Population in Alaska: >5% Peripheral: No 3

4 References Alaska Migratory Bird Co-management Council (AMBCC) Subsistence harvest survey data Available online at: Bailey, E. P Introduction of foxes to Alaskan islands--history, effects on avifauna, and eradication. U.S. Fish and Wildlife Service Resource Publication pp. Bailey, E.P. and J. L. Trapp A second wild breeding population of the Aleutian Canada Goose. American Birds, May-June p. Beyersdorf, G. S. and L. Pfaff Aleutian Canada geese in the Semidi Islands: an assessment of limiting factors. Unpubl. Rep., USFWS, AMNWR 95/07. Homer, AK. 6pp. Byrd, G. V Survey of Aleutian Canada goose nests at Chagulak and Amukta Islands, Alaska in U.S. Fish and Wildl. Serv. Rep. AMNWR, Adak, AK. 1 pp. Byrd, G. V Memorandum dated December 7, 1995, to Regional director, Region 7 transmitting minutes of the November -4, 1995, recovery team meeting. Byrd, G. V Current breeding status of Aleutian Canada Goose, a recovering endangered species. Pages 1-8 In: D.H. Rush, M.D. Samuel, D.D. Humburg and B.D. Sullivan (eds.). Biology and management of Canada geese. Proceed. International Canada goose Byrd, G. V. and J. C. Williams. 00b. Results of a survey for nesting Aleutian Canada geese on Chagulak Island in spring 00. Unpubl. Rep., U.S. Fish and Wildlife Service, AMNWR. Homer, AK. Byrd, G. V. and J. C. Williams Results of a nest survey for the restored Aleutian Canada goose on Agattu Island, Aleutian Islands, Alaska, in June 003. U.S. Fish and Wildlife Service, AMNWR 03/07. Homer, AK. Byrd, G. V. and J. C. Williams Survey of Nizki Island for Aleutian Canada Geese, June 4-6, 004, with notes on other species of birds. U. S. Fish and Wildlife Service, Alaska Maritime National Wildlife Refuge, Homer, AK Cooper, J. A The history and breeding biology of the Canada Geese of Marshy Point, Manitoba. Wildlife Monographs no. 61. Drut, M. S. and R. E. Trost Summary of goose population monitoring programs, Unpubl. Rep. for the Pacific Flyway Study Committee, U.S. Fish and Wildl. Serv., Div. of Migr. Bird. Manage., Portland, OR. Ehrlich, P. R., D. S. Dobkin, and D. Wheye Birds in Jeopardy: the Imperiled and Extinct Birds of the United States and Canada, Including Hawaii and Puerto Rico. Stanford University Press, Stanford, California. 59 pp. Gibson, D. D. and G. V. Byrd Birds of the Aleutian Islands, Alaska. Nuttall Ornithological Club, Cambridge, MA and AOU, Washington D. C. Hatch, S. A. and M. A. Hatch An isolated population of small Canada geese on Kiliktagik Island, Alaska. Wildfowl 34: Jones, R. D Buldir Island, site of a remnant breeding population of Aleutian Canada geese. Wildfowl Trust Annual 14: Migratory Bird Treaty Act (MBTA) of July 3, 1918, Ch. 18, 40 Stat. 755 (1918) (current version at 16 U.S.C ). Moser, T. J. and D. H. Rusch Age-specific breeding rates of female Interior Canada Geese. Wildlife Society Bulletin 18: Mowbray, T. B., C. R. Ely, J. S. Sedinger, and R. E. Trost. 00. Canada Goose (Branta canadensis). In: The Birds of North America, No. 68 (A. Poole and F. Gill, Eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' U Murie, O. J Fauna of the Aleutian Islands and Alaska Peninsula. United States Dept. Inter., U. S. Fish and Wildlife Service Rep. no. 61. Washington, D. C. N. Amer. Fauna 61:

5 Pacific Flyway Council (PFC) Pacific Flyway management plan for the Aleutian Canada Goose. Pacific Flyway Study Comm., Subcommittee on Aleutian Canada Geese, USFWS, Portland, OR. Unpublished Report pp. Trost, personal communication U.S. Fish and Wildlife Service (USFWS). 1980a. Selected vertebrate endangered species of the seacoast of the United States - Aleutian Canada goose. FWS/OBS-80/ U.S. Fish and Wildlife Service, Biological Services Program. 9 p. U.S. Fish and Wildlife Service (USFWS) Reclassification of the Aleutian Canada Goose from Endangered to Threatened. Status. 50 CFR 17. Text of Federal Register notice 55FR December 1, U.S. Fish and Wildlife Service (USFWS) Aleutian Canada Goose (Branta canadensis leucopareia) recovery plan. Prepared by the Aleutian Canada goose recovery team. U.S. Dept. Interior, Fish and Wildlife Service, Anchorage, AK. 55 p. U.S. Fish and Wildlife Service (USFWS). 1999c. Endangered and threatened wildlife and plants; proposal to remove the Aleutian Canada Goose from the list of endangered and threatened wildlife. Federal Register 64. U.S. Fish and Wildlife Service (USFWS). 001a. Endangered and threatened wildlife and plants; final rule to remove the Aleutian Canada goose from the Federal List of Endangered and Threatened Wildlife. March 0, 001. Federal Register 66(54): U.S. Fish and Wildlife Service (USFWS). 006c. Regulations for the 006 Alaska subsistence spring/summer Migratory Bird Harvest. Alaska Migratory Bird Co-Mgt Council, U. S. Fish and Wildlife Service, Anchorage, AK. U.S. Fish and Wildlife Service (USFWS) Waterfowl population status, 011. U.S. Department of the Interior, Washington, D.C. USA. Williams, J. C Banding, translocation and monitoring of Aleutian Canada geese in U.S. Fish and Wildlife Service Alaska Maritime National Wildlife Refuge. AMNWR 94/1, Adak, Alaska. Williams, J. C., C. Studds and G. Thomson Banding, translocation and monitoring of Aleutian Canada geese in U.S. Fish and Wildlife Service AMNWR 95/08, Adak, Alaska. Woolington, D. W., P. F. Springer and D. R. Yparraguirre Migration and wintering distribution of the Aleutian Canada geese. Pp In: Jarvis, R.L. and J.C. Bartonek (eds.). Management and biology of Pacific flyway geese: a symposium. OSU Book Version date: 1/1/01 Report authors: K. Walton, T. Gotthardt, and T. Fields Alaska Natural Heritage Program University of Alaska Anchorage Anchorage, AK For details on the development of the ASRS and criteria, please see: Gotthardt, T. A., K. M. Walton, and T. L. Fields. 01. Setting Conservation Priorities for Alaska's Wildlife Action Plan. Alaska Natural Heritage Program, University of Alaska Anchorage, AK. 5