The Condor94~454-461 0 TheCooper Ornithological Society 1992 SEVENTY-FOUR NEW AVIAN TAXA DOCUMENTED IN ALASKA 1976-1991’ DANIEL D. GIBSON AND BRINA KESSEL Universityof Alaska Museum, 907 Yukon Drive, Fairbanks, AK 99775 Abstract. The occurrencein Alaskaof 74 avian taxa wasdocumented for the first time during 1976-1991, bringingthe number of speciesknown to have occurredin Alaska to 436. Theseadded taxa include 20 speciesand eightsubspecies documented for the firsttime in North America. Key words: Bird distribution:avian taxa; Alaska. INTRODUCTION In this paper we have included only taxa doc- Continued interest in the biogeographyof Alaska umented by specimen, photograph, or tape-re- birds since Gabrielson and Lincoln’s (1959) Birds cording, which materials, except as indicated in of Alaska has rapidly increased our knowledge text, are on deposit at the University of Alaska of bird taxa that have occurred in this large and Museum (UAM). In all, we discuss74 taxa, in- geographicallyvaried region at the northwestern cluding the first documented North American extremity of the North American continent. In recordsof 20 speciesand eight subspeciesof Old their benchmark book, Gabrielson and Lincoln World birds. The Alaska list now includes 436 (1959) discussed 3 11 speciesthat had been re- species, based on the systematics of the most ported through June 1958. We updated the Alas- recent AOU Check-List (1983 and supplements). ka list through November 1977 (Kessel and Gib- In the following accounts,nomenclature in the son 1978), bringing the total to 381 species headingsdenotes whether the subject is a species (enumerated according to AOU 1957 and sup- or a subspecies.Terminology and conventions plements and Vaurie 1959, 1965). So many ad- used in describing geographic regions, abun- ditional species have been recorded since then dances, and authorities are those of Kessel and that we have prepared this addendum. Gibson (1978). All in-hand identifications are by Several factors contribute to the variety and Gibson unless stated otherwise. uniqueness of Alaska’s avifauna, including Alas- ANNOTATED LIST ka’s vast geographicextent both north-south and east-west, its varied physiography, its extensive Pelecanus erythrorhynchos Gmelin. American marine contiguity, and its proximity to the region White Pelican. A lone American White Pelican of the Bering Sea land bridge and the Old World observedby many on saltwater in Petersburgand (Kessel and Gibson 1978). Because of the re- vicinity from 2 May until the week of 13-l 7 July moteness of much of Alaska, its sheer enormity, 1981 (Osborne 1982) is Alaska’s only record of and its sparsehuman population, knowledge of a pelican. Photos were published in the local the avifauna is still far from comprehensive.Thus, newspaper(Petersburg Pilot 8[ 181:1,6 May 198 1) while a comparatively large number of species and in American Birds (35:852, 1981). This has been recorded in Alaska, the addition of new monotypic species breeds nearest Alaska in speciescontinues at a relatively rapid rate. The southern interior British Columbia (Campbell et following addendum not only includes a number al. 1990). of newly reported accidentals and casuals,but it Fregata magnificens Mathews. Magnificent also illustrates the regularity of occurrencesover Frigatebird. A juvenile Magnificent Frigatebird time of species that were formerly considered seen at close range as it flew about a ship in only accidental, and it showsthe currently chang- Belkofski Bay, Alaska Peninsula, on 15 August ing status of some species. 1985 (J. E. Low, photos)provided the first Alaska record of a fiigatebird identified to species.Iden- tification of the photos was confirmed by R. W. I Received12 November 199 1. Accepted2 1 January Schreiberand by P. Harrison. In the easternNorth 1992. Pacific, F. m. rothschildiMathews breeds no far- [4541 NEW ALASKA TAXA 455 ther north than Baja California Sur (AOU 1957), where known as far north as the Queen Charlotte but it wanders much farther north (e.g., Langara Islands (Campbell et al. 1990). Island, British Columbia, August 1981, Camp- At a different extremity of the state and at bell et al. 1990). Unidentified frigatebirds have another season-in Southwestern Alaska and in been reported at intervals in the northern Gulf early summer-the carcass of a breeding-plu- ofAlaska (at sea,July 1957 and September 1969, maged Cattle Egret was salvaged at Agattu Is- Isleib and Kessel 1973; in Montague Strait, Prince land, Aleutians, on 19 June 1988 (B. Seppi and William Sound, 26-27 June 1984, C. Kimer; and E. V. Klett). The specimen (UAM 5553, female) in Chiniak Bay, Kodiak Island, 27 June 1984, J. was identified as Asiatic B. i. coromanda (Bod- and D. Brigham). daert) by the cinnamon-colored ornamental Zxobrychussinensis (Gmelin). Yellow Bittern. feathering over the entire head (including cheek, A Yellow Bittern observed by many at Attu Is- chin, and throat) and on foreneck, breast, and land, Aleutian Islands, 17-22 May 1989 is the back and by its large size (diagonal tarsus 9 1.4 only Alaska record of this eastern Palearctic her- mm). In a distribution wholly disjunct from that on (UAM 56 11, female). This monotypic species of nominate ibis, B. i. coromanda breeds in breeds as far north and east as northern Japan southern and southeastern Asia (Vaurie 1965, and the southern Kurile Islands (Vaurie 1965). Cramp and Simmons 1977), as far eastand north Casmerodius albus (Linnaeus). Great Egret. as central Japan (Brazil 1991). Alaska’s first record of a Great Egret was a bird Butorides striatus (Linnaeus). Green-backed near Juneau on 22 June 1980 (F. A. Glass and Heron. A Green-backed Heron stalking about a R. H. Armstrong, photos). Another was reported small pond near Juneau on 29 May 1983 (L. L. at Cordova on 14 May 1984 (J. L. Trapp). Sub- Hawkins, photos) provided Alaska’s first record. sequently, single birds were observed at Glacier Western Nearctic B. s. anthonyi (Meams) breeds Bay from 19 May through 3 July 1987 (B. B. as close to Alaska as southwestern British Co- Paige)and at Kodiak Island from 19 May through lumbia (Godfrey 1986). early July 1987 (R. A. Macintosh, J. B. Allen, Nycticorax nycticorax (Linnaeus). Black- and D. W. Menke, photos). The likely subspe- crowned Night-Heron. Like the Cattle Egret, the cies, New World C. a. egretta (Gmelin), breeds Black-crowned Night-Heron has reached Alaska no closer to Alaska than Washington; it is a very from two different populations. The only docu- rare visitant in southern British Columbia and mented records are an adult observed at Attu is accidental in the Queen Charlotte Islands Island, Aleutians, on 20 April 1986 (G. F. Wag- (Campbell et al. 1990). Both Palearctic races, ner, photos) and a flock of up to eight birds ob- widespread C. a. albus and eastern C. a. modes- served at Juneau 17 May-4 July 1987 (M. E. tus (Gray), occur as far east as Japan, the former Isleib and others, photos). Three other Bering as a visitant and the latter as a breeder (Vaurie Sea reports, all of adults, include one at Atka 1965). Island, Aleutians, on 28 April 1975 (fide A. W. Bubulcusibis (Linnaeus). Cattle Egret. The first White); one at St. Paul Island, Pribilof Islands, Alaska record of the Cattle Egret comprised four on 3 April 1979 (N. Stepetin); and one at Shemya birds in the Ketchikan area in November 1981 Island, Aleutians, on 25 April 198 1 (T. G. Tobish (Gibson and Hogg 1982). Two birds (UAM 4 165- and G. B. Rosenband). The Juneau record is the 4166) were found dead, one of which had been only Alaska report from east of the Bering Sea. banded in California as a nestling in June 198 1. The Palearctic subspecies,nominate nyctico- Since 198 1 Cattle Egretshave occurred in south- rax, breeds as far east as central Japan (Brazil eastern Alaska in three years: single birds in No- 199 1) and is presumably the form taken once in vember 1984 at Ketchikan (R. E. Wood and C. the Commander Islands (female, 27 May 1960, Smith), Sitka (C. H. Johnstone), and Peril Strait Marakov 1962). North American N. n. hoactli (L. J. Johnson); one in December 1986 at Sitka (Gmelin) is a rare local breeder and summer and (K. Hanson, photo); and one in December 1989 winter visitant in southern British Columbia at Ketchikan (R. E. Wood). The Ketchikan spec- (Godfrey 1986, Campbell et al. 1990). The latter imens are nominate ibis, the Cattle Egret that has subspecieswas recognized by the AOU (1957), colonized North America over the last 50 years but was submerged in nominate nycticorax by (AOU 1957, 1983); it is a scarce late-fall and Payne (1979). winter visitant on the British Columbia coast, Mergus mergansermerganser Linnaeus. Com- 456 DANIEL D. GIBSON AND BRINA KESSEL mon Merganser. The first Alaska record of the August 1984 (J. M. Wright and others, photos) widespread Palearctic subspecies of the Com- is the only subsequent documented sighting. mon Merganser included two adult males (UAM A primary remex and three rectrices collected 3438, 3546) taken at Shemya Island, Aleutians, in an abandoned building at Attu in May 1987 in May 1976 and reported by Byrd et al. (1978) (T. G. Tobish) and identified by R. C. Layboume and by Gibson (198 l), who described this form as those of a “young” Northern Hobby constitute as a rare, annual spring migrant in the western the only specimen evidence of this species’ oc- Aleutians. An adult male (F. H. Fay, photos) was currence in Alaska (UAM 5647). Nominate sub- found dead at Punuk Islands, St. Lawrence Is- buteois the form of the entire range of this wide- land, on 29 June 1979 (Kessel 1989). spread Palearctic bird, except for parts of China; Cuthartes aura (Linnaeus).