Status of Hudsonian Godwits on the Yukon-kuskokwim Delta, Alaska

Over 100 observations of the Hudsonian Godwit (Limosa haemastica) on the Yukon-Kuskokwim Delta in western Alaska since 1983 show that the species is a fairly common migrant, uncommon summer visitant, and rare, perhaps locally uncommon, breeder there.Spring arrival and fall departure dates are among the earliest and latest, respectively, in Alaska.Observations of breeding behavior and/or recently fledged young provide compelling evidence for breeding at 5 sites.Although some probable breeders are found along the taiga-tundra ecotone described as breeding habitat for the species elsewhere, others use dwarf-shrub meadows well beyond treeline.Postbreeding birds are usually found in low numbers, but occasional aggregations of 00 Hudsonian Godwits are among the largest concentrations of this species reported in Alaska.The Yukon-Kuskokwim Delta may support a significant fraction of the Hudsonian Godwit population in Alaska.The Hudsonian Godwit is considered a species of high conservation concern (Brown et al. 2000), in part because of the isolation of its major breeding populations.It breeds in three disjunct regions of North America, Hudson Bay, northwestern Northwest Territories, and Alaska (Hayman et al. 1986), but our understanding of its breeding biology is derived almost exclusively from a single study near Churchill, Manitoba (Hagar 1966).In comparison to that among other shorebird species, gene flow among Hudsonian Godwit populations is very low, and the level of genetic differentiation among the three populations is one of the highest reported for any species of bird (Haig et al. 1997).These disjunct populations almost certainly differ in their migration strategies (Kessel and Gibson 1978) and may differ in use of breeding and staging habitats as well.Because of the potential differences among populations at the continental level, populationspecific investigations are needed if effective conservation strategies are to be planned and implemented.The value of population-specific data applies at smaller spatial scales as well.Within Alaska, current information suggests that Hudsonian Godwits may occur in disjunct populations separated by hundreds of kilometers.The species is a confirmed breeder only in south-central Alaska around Cook Inlet (Williamson and Smith 1964, Kessel and Gibson 1978).It is also considered an uncommon probable breeder 600-900 km northwest of Cook Inlet around Kotzebue and Norton sounds (Kessel and Gibson 1978) and a possible rare breeder at the base of the Seward Peninsula (Kessel 1989).Although these Alaska populations appear to be separated geographically, and may be separated genetically, the relative paucity of ornithological field work across much of the intervening distance has not allowed for a test of these hypotheses.The Yukon-Kuskokwim Delta is between the two known or suspected centers of breeding in Alaska, situated immediately south of Norton Sound and 500 km west of Cook Inlet.As a result, the status of the species in this

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