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The use of keratinized tissues (e.g., hair, claws) to investigate physiological effects of environmental and anthropogenic stressors in free-ranging wildlife populations has increased because these tissues retain steroid hormones during growth and are relatively easy to collect and store in the field. We measured reproductive and stress-related steroid hormones in wolves (Canis lupus ligoni; n = 31) captured on Prince of Wales Island, Alaska, USA, during 1993–1994 and 2012–2014, representing periods of time when both wolf harvest and densities ranged from high to moderate. We validated enzyme immunoassay kits to measure steroid hormone concentrations in wolf guard hair, undercoat hair, and claw tip samples. Progesterone, testosterone, and cortisol were extracted and measured in the 3 keratinous tissues from wolves of different age class, sex, residency status, and collection periods. Within each tissue type, progesterone and testosterone were positively correlated (guard hair, r = 0.59, P = 0.003; undercoat hair, r = 0.55, P = 0.011; claws, r = 0.62, P ≤ 0.001) and cortisol concentrations were not related to either reproductive hormone. We were able to measure hormone concentrations in archived keratinous tissues collected up to 25 years earlier to assess stress and reproductive activity in historical samples. Our study validates a method for measuring steroid hormones in hair, and for the first time, continuously growing claws in wolves. Measurement of hormone concentrations in keratinous tissues may aid in the assessment of reproductive activity and physiological stress responses in wolf populations over long-term time periods (i.e., decades) to enhance conservation efforts of an important apex predator.

Although ungulates are the main prey of wolves (Canis lupus) throughout their range, substantial dietary diversity may allow wolves to persist even when ungulates are declining or rare. Alexander Archipelago wolves (Canis lupus ligoni) inhabit distinct mainland and island biogeographic units, each with a unique assemblage of available prey. We quantified biogeographic variability in wolf diets across the archipelago using DNA metabarcoding of prey in 860 wolf scats collected during 2010–2018 in 12 study sites. We hypothesized that wolves would increase their dietary diversity and niche breadth as the proportion of ungulate species in their diets decreased, but that this could be mediated by the availability of coastal resources. Application of DNA metabarcoding achieved fine taxonomic resolution of prey remains and identified 55 diet items representing species from 42 genera and 29 families, many previously undetected in coastal wolf diets. Overall, ungulates made up the largest proportion of wolf diets but were also most variable between study sites (occurrence per item index [O/I] = 0.130–0.851). On islands, Sitka black‐tailed deer (Odocoileus hemionus) were the most consumed ungulate species, whereas moose (Alces alces) and mountain goats (Oreamnos americanus) contributed more to mainland wolf diets. Wolves responded to biogeographical variation in availability of their primary prey by altering their foraging patterns. Wolves increased the number and diversity of species consumed and widened their dietary niche as the proportion of ungulates in their diet declined rather than prey switch to one or few individual diet items. Across all study sites combined, beaver (Castor canadensis; O/I = 0.125), marine mammals (O/I = 0.113), and black bears (Ursus americanus; O/I = 0.067) were important alternate prey. In areas where ungulates had become scarce, sea otters (Enhydra lutris) were particularly important, in one case even becoming the primary diet item suggesting that the ongoing expansion of sea otter populations postreintroduction restores an important food source for these cryptic predators. Here, we show extensive variation in the diet of wolves and elucidate regional consumer–resource interactions across an archipelagic landscape.

Recent field work in the Petersburg Borough of southeastern (SE) Alaska has led to the discovery of two species of lichenized fungi in the Ostropales that are here described as new to science: Jamesiella dacryoidea Fryday, which has green-grey dacryoid thlasidia, and Sagiolechia bairdensis Fryday, which has very small apothecia (<0.2 mm diam.), 3-septate ascospores and a trebouxioid photobiont. A key to the North American species of Sagiolechia and Gyalidea is also provided. In addition, Bryobilimbia ahlesii (Hepp) Fryday, Printzen & S.Ekman is reported for the first time from Alaska, along with records of several other species that have rarely been collected in the state.

The interpretation of the extent of late Wisconsin glaciation in southeastern Alaska has varied between geologists and biologists. Maps and reports of the region prepared by geologists commonly indicated that late Wisconsin ice extended as a large uniform front west to the edge of the continental shelf. However, the distribution of plants and animals in the region has led many biologists to suggest that there may have been ice-free areas that served as refugia during the late Wisconsin. Based on analyses of aerial photographs, topographic maps, and bathymetric charts, in conjunction with a review of previous literature and reconnaissance fieldwork throughout the region, this study presents data supporting a limited ice extent in the Alexander Archipelago during the late Wisconsin and identifies possible ice-free areas that may have served as refugia. These areas include (1) the Fairweather Ground, (2) the Herbert Graves Island area, (3) the western coast of southern Baranof Island and adjacent continental shelf, (4) Coronation Island and the adjacent continental shelf, (5) the Warren Island area, (6) the continental shelf from west of Heceta Island to Forrester Island in the south, (7) parts of the west coast of southern Dall Island, and (8) lowland areas in southern Prince of Wales Island. The identification of these possible refugia has bearing on the recolonization of the Alexander Archipelago, as they could have served as centers of biotic dispersal upon regional deglaciation and as stepping stones for early humans with a maritime tradition entering the western hemisphere from Asia.

We used tetracycline biomarking, augmented with genetic methods to estimate the size of an American black bear (Ursus americanus) population on an island in Southeast Alaska. We marked 132 and 189 bears that consumed remote, tetracycline-laced baits in 2 different years, respectively, and observed 39 marks in 692 bone samples subsequently collected from hunters. We genetically analyzed hair samples from bait sites to determine the sex of marked bears, facilitating derivation of sex-specific population estimates. We obtained harvest samples from beyond the study area to correct for emigration. We estimated a density of 155 independent bears/100 km2, which is equivalent to the highest recorded for this species. This high density appears to be maintained by abundant, accessible natural food. Our population estimate (approx. 1,000 bears) could be used as a baseline and to set hunting quotas. The refined biomarking method for abundance estimation is a useful alternative where physical captures or DNA-based estimates are precluded by cost or logistics.

We examined the population genetics and phylogenetics of Falcipennis canadensis isleibi, a subspecies of Spruce Grouse from the Alexander Archipelago of southeast Alaska, which was recently given subspecies status on the basis of subtle differences in plumage coloration and its limited distribution on several islands. The taxonomic status of Fc. isleibi is particularly consequential, both because little is known about its evolutionary, demographic, and conservation status and because island endemics often face high extinction risks. Samples were collected from central Alaska, British Columbia, and Prince of Wales (POW) and Zarembo (ZAM) islands in the Alexander Archipelago and identified to subspecies using established morphological traits. We sequenced the cytochrome-c oxidase I (COI) subunit of the mitochondrial genome (n = 62) and genotyped each individual at six nuclear microsatellite loci (n = 65). Individuals from POW and ZAM shared a unique mitochondrial haplotype not observed in other populations of other subspecies (F. c. franklinii and F. c. canadensis), whereas haplotypes were shared by individuals identified as franklinii or canadensis. Microsatellite loci revealed significant divergence among all subspecies populations ( = 0.352) as well as divergence between POW and ZAM populations of F. c. isleibi. These data corroborate the morphological classification of F.c. isleibi as a separate subspecies. Spruce Grouse are not managed as a single species by the state of Alaska, but instead as an aggregate with other forest grouse species. Our results indicate that populations of F.c. isleibi warrant special management attention to maintain this distinct evolutionary lineage.

The Alexander Archipelago wolf (Canis lupus ligoni) is unique to southeast Alaska, occurring on islands south of Frederick Sound and along the mainland between Dixon Entrance and Yakutat Bay. Sitka black-tailed deer (Odocoileus hemionus sitkensis) are an important prey species for wolves across the southern part of the region. Spawning salmon (Onchorynchus sp.) are seasonally available but their presence in wolf diets has not previously been quantified. We examined the range of bone collagen δ13C and δ15N values for wolves throughout southeast (n = 163) and interior (n = 50) Alaska and used a dual-isotope mixing model to determine the relative contribution of salmon-derived marine protein in the diet. Southeast Alaska wolves consumed significantly more salmon (mean ± SE: 18.3 ± 1.2%) than did wolves from interior Alaska (9.1 ± 0.6%, P<0.001). Wolves on the southeast Alaska mainland appeared to have higher marine isotopic signatures than island wolves, although this difference was not significant. Variation among individual wolf diets was higher for southeast than for interior Alaska wolves, and variation was highest in coastal mainland wolf diets (P<0.001). Marine resources may augment the diet of southeast Alaska wolves during seasonal or annual fluctuations in the availability of deer, particularly in those areas on the mainland where densities of terrestrial ungulates are relatively low.

Northern Goshawks occupying the Alexander Archipelago, Alaska, and coastal British Columbia nest primarily in old-growth and mature forest, which results in spatial heterogeneity in the distribution of individuals across the landscape. We used microsatellite and mitochondrial data to infer genetic structure, gene flow, and fluctuations in population demography through evolutionary time. Patterns in the genetic signatures were used to assess predictions associated with the three population models: panmixia, metapopulation, and isolated populations. Population genetic structure was observed along with asymmetry in gene flow estimates that changed directionality at different temporal scales, consistent with metapopulation model predictions. Therefore, Northern Goshawk assemblages located in the Alexander Archipelago and coastal British Columbia interact through a metapopulation framework, though they may not fit the classic model of a metapopulation. Long-term population sources (coastal mainland British Columbia) and sinks (Revillagigedo and Vancouver islands) were identified. However, there was no trend through evolutionary time in the directionality of dispersal among the remaining assemblages, suggestive of a rescue–effect dynamic. Admiralty, Douglas, and Chichagof island complex appears to be an evolutionarily recent source population in the Alexander Archipelago. In addition, Kupreanof island complex and Kispiox Forest District populations have high dispersal rates to populations in close geographic proximity and potentially serve as local source populations. Metapopulation dynamics occurring in the Alexander Archipelago and coastal British Columbia by Northern Goshawks highlight the importance of both occupied and unoccupied habitats to long-term population persistence of goshawks in this region.

We studied den use and den-habitat selection by the Prince of Wales Island flying squirrel (Glaucomys sabrinus griseifrons) at multiple spatial scales in fragmented temperate rain-forest habitats because of the role dens play in the distribution, reproduction, and population density of this endemic subspecies. We observed differences in spatial patterns associated with den use between juveniles and adults: juvenile core denning areas were almost an order of magnitude larger than those of adults, and juveniles used about one-half the number of dens per month as adults. Female juveniles exhibited both the largest mean and maximum movements between consecutive dens among all age and sex classes. At the microhabitat scale of den selection snags were not selected over live trees, but flying squirrels primarily used cavities in snags and live trees. Flying squirrels also selected dens in the largest diameter live trees and snags, in snags with intermediate levels of decay, in live trees with more conks and visible bole entries, and in western hemlock (Tsuga heterophylla). At the broader scale of den selection flying squirrels chose den locations in neighborhoods with higher-volume forests and lower levels of fragmentation, although not lower absolute amounts of edge, than was available across the landscape. Our results suggest that extensive modification of landscapes from clear-cut logging and the creation of an early-seral matrix appeared to influence spatial patterns of den use in flying squirrels and den selection at the broader scale. When compared to patterns in a more-intact landscape, den selection at the microhabitat scale did not relate to differences in landscape context, suggesting additional factors might play an important role in den use across the region.

Human-mediated movement of wildlife is a common practice in North America. Some translocations have occurred where local populations were thought to be extinct or simply not present. In Alaska’s Alexander Archipelago, mountain goats ( Oreamnos americanus ) were not considered indigenous and were introduced to Baranof Island in 1923. However, a range-wide survey using microsatellites and mitochondrial DNA revealed a distinct genetic subpopulation endemic to the island. In this study, we attempted to clarify the evolutionary history of the mountain goats on Baranof Island by examining sequence variation in the Y chromosome. We first screened five regions of the Y chromosome in a subset of mountain goats from across their native range. We detected a single polymorphic site in the SRY promoter, and subsequently sequenced this gene in 100 mountain goats. A unique Y chromosome polymorphism was restricted to Baranof Island and an area near Haines, Alaska, and not detected in the presumed source population. An island-to-mainland dispersal scenario from a cryptic refugial population during the retreat of the Cordilleran ice-sheet would account for this distribution. Overall, these data support the hypothesis that a glacial relict population of mountain goats was present on the island prior to introduction. Based on a combination of mitochondrial, microsatellite, and Y chromosome data, we recommend recognizing Baranof Island mountain goats as an evolutionary significant unit.