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Alexander V. Kondratyev

Publications and source records attributed to Alexander V. Kondratyev.

8 recordsLinked to original sources

As the goose flies: Migration routes and timing influence patterns of genetic diversity in a circumpolar migratory herbivore

Migration schedules and the timing of other annual events (e.g., pair formation and molt) can affect the distribution of genetic diversity as much as where these events occur. The greater white-fronted goose ( Anser albifrons ) is a circumpolar goose species, exhibiting temporal and spatial variation of events among populations during the annual cycle. Previous range-wide genetic assessments of the nuclear genome based on eight microsatellite loci suggest a single, largely panmictic population despite up to five subspecies currently recognized based on phenotypic differences. We used double digest restriction-site associated DNA (ddRAD-seq) and mitochondrial DNA (mtDNA) sequence data to re-evaluate estimates of spatial genomic structure and to characterize how past and present processes have shaped the patterns of genetic diversity and connectivity across the Arctic and subarctic. We uncovered previously undetected inter-population differentiation with genetic clusters corresponding to sampling locales associated with current management groups. We further observed subtle genetic clustering within each management unit that can be at least partially explained by the timing and directionality of migration events along with other behaviors during the annual cycle. The Tule Goose ( A. a. elgasi ) and Greenland subspecies ( A. a. flavirostris ) showed the highest level of divergence among all sampling locales investigated. The recovery of previously undetected broad and fine-scale spatial structure suggests that the strong cultural transmission of migratory behavior restricts gene flow across portions of the species’ range. Our data further highlight the importance of re-evaluating previous assessments conducted based on a small number of highly variable genetic markers in phenotypically diverse species.

Circumpolar Arctic↗

Circumpolar variation in morphological characteristics of Greater White-fronted Geese Anser albifrons

Capsule: Greater White-fronted Geese show significant variation in body size from sampling locations throughout their circumpolar breeding range. Aims: To determine the degree of geographical variation in body size of Greater White-fronted Geese and identify factors contributing to any apparent patterns in variation. Methods: Structural measures of >3000 geese from 16 breeding areas throughout the Holarctic breeding range of the species were compared statistically. Results: Palearctic forms varied clinally, and increased in size from the smallest forms on the Kanin and Taimyr peninsulas in western Eurasia to the largest forms breeding in the Anadyr Lowlands of eastern Chukotka. Clinal variation was less apparent in the Nearctic, as both the smallest form in the Nearctic and the largest form overall (the Tule Goose) were from different breeding areas in Alaska. The Tule Goose was 25% larger than the smallest form. Birds from Greenland (A. a. flavirostris) were the second largest, although only slightly larger than geese from several North American populations. Body size was not correlated with breeding latitude but was positively correlated with temperature on the breeding grounds, breeding habitat, and migration distance. Body mass of Greater White-fronted Geese from all populations remained relatively constant during the period of wing moult. Morphological distinctness of eastern and western Palearctic forms concurs with earlier findings of complete range disjunction. Conclusions: Patterns of morphological variation in Greater White-fronted Geese across the Holarctic can be generally attributed to adaptation to variable breeding environments, migration requirements, and phylo-geographical histories.

Bird Study↗

Moult migration of emperor geese Chen canagica between Alaska and Russia

We studied reproductive success and post-breeding movements of 32 adult female emperor geese Chen canagica that were marked with satellite radio transmitters on their nesting area on the Yukon-Kuskokwim Delta (YKD), Alaska 2000–2004. All 16 females that failed to successfully reproduce departed the YKD and moulted remiges either on the north coast of the Chukotka Peninsula, Russia (n=15), or on St. Lawrence Island, Alaska (n=1). Of 16 females that successfully nested, one migrated to Russia following hatch whereas the remainder stayed on the YKD. While moulting on the Chukotka Peninsula, emperor geese with satellite transmitters primarily used coastal lagoons west of Kolyuchin Bay. We observed 21,150 adult-plumaged emperor geese during aerial surveys in Chukotka in 2002. Most (95%) were in the same region used by geese that had been marked with satellite transmitters in Alaska. The number of emperor geese observed in Russia was comparable to our estimate of ≥20,000 adults that either do not nest or nest unsuccessfully each year on the YKD, suggesting that most nonproductive adults, or ≥28% of the adult population departs the YKD to moult elsewhere. The number of moult migrants may be substantially higher in years of poor reproductive success or if adult-plumaged birds that are not of breeding age also leave the YKD. Moult migration of emperor geese between Alaska and Russia is likely substantially greater than previously believed. Russian moulting habitats are important to the North American population of emperor geese and events that affect survival of geese in Russia could impact population trends on the YKD. Protection of coastal lagoons on the north coast of Chukotka is warranted.

Journal of Avian Biology↗

Evidence of Emperor Geese breeding in Russia and staging in Alaska

Emperor Geese ( Chen canagica ) breed primarily on the Yukon-Kuskokwim Delta, Alaska (Eisenhauer and Kirkpatrick 1977), but a small, poorly quantified proportion of the world's population is known to breed in the Russia Far East (Kistchinski 1976, 1988, Portenko 1981). Eisenhauer and Kirkpatrick (1977) stated that 80 to 90% of all Emperor Geese breed on the Yukon-Kuskokwim Delta, Alaska, and current estimates for numbers of breeding pairs in this area are 20,000 to 25,000 (R. A. Stehn, National Biological Service, Anchorage, Alaska, unpubl. data). In Russia, Emperor Geese are distributed primarily along the north coast of the Chukotka Peninsula between Kolyuchin Bay and Cape Shmidt, and in the Anadyr Lowlands along the coast of Anadyr Bay (Fig. 1; Kistchinski 1988, Kondratyev 1992, 1993), Kistchinski (1976) noted that up to 80% of these geese are nonbreeding birds. Recent aerial surveys of Emperor Goose habitats along the eastern coast of Russia indicated a minimum of 3,000 to 5,000 geese, although very few were on nests or with young, and only 127 total broods were seen during these surveys (J. I. Hodges, Fish and Wildlife Service (FWS), Juneau, Alaska, unpubl. data) It is not known if these two continental distributions of breeding Emperor Geese commingle and use similar areas during migration and for winter. Aerial surveys of the Alaska Peninsula during spring and fall indicate that lagoons on the northern coast are the primary staging areas for this species, and it is presumed that virtually all Emperor Geese use the Alaska Peninsula during migration (Petersen and Gill 1982). Emperor Geese winter throughout the Aleutian and Kommandorsky islands (Byrd et al., 1974). In the late fall, geese arrive in the western and eastern Aleutian Islands before arriving in the central Aleutians, thus suggesting that geese may be coming to this wintering area from both continents (G. V. Byrd pers, comm.). Speculations of previous investigators that Emperor Geese breeding in Russia use the Alaska Peninsula for staging (Eisenhauer and Kirkpatrick 1977, A. Krechmar pers. comm.) have not been confirmed. Here we report observations of two geese banded as juveniles in Russia and observed on the Alaska Peninsula during their first fall migration.

Alaska↗

A seabird monitoring program for the North Pacific

Seabird monitoring is the accumulation of time series data on any aspect of seabird distribution, abundance, demography, or behavior. Typical studies include annual or less frequent measures of numbers or productivity; less commonly, the focus is on marine habitat use, phenology, food habits, or survival. The key requirement is that observations are replicated over time and made with sufficient precision and accuracy to permit the meaningful analysis of variability and trends. Along the Pacific coast of North America, seabird monitoring has consumed substantial amounts of public funding since the early 1970s. The effort has been largely uncoordinated among the many entities involved, including provincial, state, and federal agencies, some private organizations, university faculty, and students. We reaffirm the rationale for monitoring seabirds, review briefly the nature and accomplishments of the existing effort, and suggest actions needed to improve the effectiveness of seabird monitoring in the Pacific. In particular, we propose and describe a comprehensive Seabird Monitoring Database designed specifically to work with observations on seabird population parameters that are replicated over time.

Transactions of the North American Wildlife and Na↗

The status of sea ducks in the North Pacific Rim: Toward their conservation and management

Sea ducks (tribe Mergini after Johnsgard 1960) are the most northerly distributed ducks, and species diversity is greatest in the North Pacific. They exploit a diversity of inshore and offshore marine habitats during the non-breeding season, and their use of habitat during breeding varies from coastal through freshwater wetlands of the tundra and taiga (Figure 1, Appendix 1). Non-breeding cohorts frequent marine habitats most of the year. Sea ducks thus are important indicators of the quality of freshwater and marine ecosystems of northern biomes. Of the 17 species discussed in this manuscript, at least 3 are reported to be declining (Appendix 2). However, the basis for many of those assessments is equivocal because there has been little effort to monitor populations. The efforts to more precisely assess their status point to catastrophic declines (Kertell 1991, Stehn et a 1993). Conservation problems related to sea ducks have a long history throughout the Holarctic. For example, the Labrador duck ( Camptorhynchus labradorius ) became extinct in 1875. (Phillips 1925); common eiders ( Somateria mollissima ) declined seriously throughout the northern hemisphere (Townsend 1914, Phillips 1925, Doughty 1979); harlequin ducks ( Histrionicus histrionicus ) experienced declines in Iceland and Greenland (Gudmundsson1971, Salomonson 1950), and more recently have been designated endangered in eastern Canada (Committee On the Status of Endangered Wildlife in Canada 1990). In Russia, all species of eider and harlequin ducks have been closed to sport hunting since 1981, and the Chinese mergansers ( Mergus squamatus ) presently are extremely rare and fully protected, i.e. category one of the red book (Solomonov 1987).

Transactions of the North American Wildlife and Na↗