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In seasonally varying environments, animals should alter habitat selection through time to avoid the harshest conditions. Winter severity is limiting for many ungulates in high-latitude ecosystems, and quality of habitat is an important determinant of winter survival. Previous studies in Southeast Alaska indicated that Sitka black-tailed deer (Odocoileus hemionus sitkensis) selected old-growth forest that provides both snow interception and forage, but with great variability among studies, years, and geographic areas. Clearcut timber harvest has greatly reduced the extent and quality of old-growth forest. The value of 2nd-growth and old-growth forest types to deer likely depends on snow depth, which is highly variable in space and time. We measured selection for vegetation classes, landscape features, and forage biomass by monitoring 56 GPS-radiocollared adult female deer from 1 January to 1 April between 2011 and 2013. Simultaneously, we measured snow depth across deer home ranges daily. We determined that snow depth had a strong effect on selection for vegetation classes. During periods of low snow, deer selected young 2nd growth but avoided old 2nd growth and high-volume old growth. As snow depths increased, young 2nd growth was avoided and deer selected old 2nd-growth and productive old-growth forests. The composition of vegetation classes within the landscape influenced selection, with deer selecting locally abundant habitats. These behaviors suggest that the widespread distribution of forest patches that provide snow interception and forage biomass may be critical to fulfilling the energetic requirements of deer during winters with snow. Such context-dependent habitat selection is likely widespread among wildlife species in variable environments and should be incorporated into study design and analysis.

Summary 1. Neonate survival is a key life history trait, yet remains challenging to measure in wild populations because neonates can be difficult to capture at birth. Estimates of survival from neonates that are opportunistically captured might be inaccurate because some individuals die before sampling, resulting in data that are left truncated. The resulting overestimation of survival rates can further affect ecological inference through biased estimates of covariate effects in survival models, yet is not addressed in most studies of animal survival. Here, we quantify the effects of left truncation on survival estimates and subsequent ecological inference. 2. Vaginal implant transmitters (VITs) enable capture of ungulates at birth, yielding data without left truncation. The effects of left truncation on survival estimation were quantified using age-dependent survival models for VIT and opportunistically captured neonatal deer. Differences in daily survival rates (DSRs) and cumulative survival probability were calculated for the first 70 days of life. In addition, left truncation was simulated by removing fawns that died during the first 1 or 2 days of life from the VIT-caught sample, isolating the effect of left truncation. 3. Cumulative probability of survival during the first 70 days of life was overestimated by 7–23% for fawns caught opportunistically compared with those caught by VIT, depending on model design. Differences in DSRs were large at age 1 day, but had converged by age 30 days. Simulated left truncation resulted in overestimates of survival of up to 31%. Model selection and covariate coefficients were strongly affected by left truncation, producing spurious ecological inference, including changes to sign and/or magnitude of inferred effects of all covariates. 4. We recommend (i) every effort be made to capture neonates; (ii) consistent capture methods, using at least in part non-truncating techniques, be implemented across years and study areas; and (iii) exclusion of left-truncated data from survival estimates until DSRs converge with those calculated from non-truncated data. This work emphasizes the importance of accounting for left truncation in survival estimation for any species with strong age-dependent survival in order to prevent biased conclusions produced by sampling method rather than true ecological effects.

We developed an original modeling approach using program Stella® to investigate the usefulness of predator–prey ratios (PPRs) for interpreting top-down and bottom-up forcing on moose Alces alces. We included density-dependent feedbacks for the moose population, allowed K to vary based on amount and quality of available forage for moose, integrated effects of compensatory mortality, and added time lags in wolves Canis lupus tracking the moose population. Modeling scenarios we developed included bottom-up and top-down regulation as predetermined outcomes. We then evaluated whether PPRs would reflect the various combinations of trajectories of predator and prey populations under top-down versus bottom-up regulation. The resulting patterns of PPRs were impossible to disentangle from one another, and did not provide reliable insights into whether top-down or bottom-forcing occurred, especially over short time spans where critical decisions related to management of moose and wolves might be necessary. Only under top-down regulation did PPRs reflect the degree of predation experienced by moose, but in that instance, knowledge of top-down regulation must be known a priori to correctly interpret PPRs. Potential problems with interpreting PPRs include their double-variable nature, which resulted in the failure to reflect patterns of increase and decrease for predators and prey. We suggest that confidence intervals for PPRs be calculated from a binomial, similar to that proposed for sex and age ratios, which should help discourage the inappropriate use of this metric. We caution that the temptation to use PPRs often is irresistible, but their reliability is highly questionable. We provide an alternative method to using PPRs or other predation metrics for determining whether top-down or bottom-up forcing is occurring by adopting an approach based on the physical condition and life-history characteristics of prey.

We examined the roles of sex and spatial scale in habitat selection by Alaskan moose Alces alces gigas. We GPS-collared 11 female and seven male adult moose in the Tongass National Forest, Alaska, USA, during 2002-2004. We predicted that adult male and female moose would be spatially separated outside of the mating season, consistent with hypotheses attributing sexual segregation among sexually dimorphic ruminants to allometric differences in body and gastrointestinal size, and resulting differential needs for nutrient requirements by the sexes (the gastrocentric hypothesis), and varying risks of predation (the predation hypothesis) between sexes, especially for females with young. We predicted that habitat selection would be similar between sexes during the mating season, but dissimilar and occur at different scales during periods of late gestation and lactation. We expected that during segregation, females would select for a higher percentage of forested cover and a higher edge density than mal...

Densely vegetated environments have hindered collection of basic population parameters on forest-dwelling ungulates. Our objective was to develop a mark—recapture technique that used DNA from fecal pellets to overcome constraints associated with estimating abundance of ungulates in landscapes where direct observation is difficult. We tested our technique on Sitka black-tailed deer (Odocoileus hemionus sitkensis) in the temperate coastal rainforest of Southeast Alaska. During 2006–2008, we sampled fecal pellets of deer along trail transects in 3 intensively logged watersheds on Prince of Wales Island, Alaska. We extracted DNA from the surface of fecal pellets and used microsatellite markers to identify individual deer. With genotypes of individual deer, we estimated abundance of deer with moderate precision (±20%) using mark—recapture models. Combining all study sites, we identified a 30% (SE = 5.1%) decline in abundance during our 3-year study, which we attributed to 3 consecutive severe winters. We determined that deer densities in managed land logged >30 years ago (7 deer/km2, SE = 1.3) supported fewer deer compared to both managed land logged

We tested a protocol for extracting DNA from fecal pellets from Sitka black-tailed deer (Odocoileus hemionus sitkensis) and evaluated genotyping performance of previously developed microsatellite markers as well as a suite of new markers designed specifically for this study. We screened 30 microsatellites, and identified 7 (23%) loci including 4 new markers, that fit well into a single multiplex and consistently genotyped deer with low error rates. DNA was extracted from 2,408 fecal-pellet samples. Of those, 1,240 (52%) were genotyped successfully at all 7 markers allowing identification of 634 genetically unique deer. Using DNA from fecal pellets collected in the field was an effective technique for identifying and distinguishing among deer.

We investigated the influence of habitat use on risk of death from hunting and trapping of 55 radiocollared gray wolves (Canis lupus) from an exploited insular population in Southeast Alaska, USA. We compared mortality rates for resident and nonresident wolves and used Cox proportional hazards regression to relate habitat composition within 100-m circular buffers around radiolocations to risk of death of resident and nonresident wolves. In addition, we included covariates representing distances to roads, logged stands, and lakes and streams in those analyses. We also compiled harvest data from 31 harvest units within the study area to compare densities of roads and distances from human settlements with rates of harvest. During our study 39 wolves died, of which 18 were harvested legally, 16 were killed illegally, and 5 died from natural causes. Legal and illegal harvest accounted for >87% of the mortality of radiocollared resident and nonresident wolves. Mean annual survival was 0.54 (SE = 0.17) for all wolves. Annual survival was 0.65 (SE = 0.17) for resident wolves and 0.34 (SE = 0.17) for nonresidents. Very few (19%) nonresident wolves survived to colonize vacant territories or join existing wolf packs. Roads, muskegs, and distances from lakes and streams were covariates positively associated with death of resident wolves. Clear-cuts were positively associated with risk of death of nonresident wolves. Rate of harvest increased with density of roads; however, road densities >0.9 km/km2 had little additional effect on harvest rates. Harvest rates decreased with ocean distances from nearest towns or settlements. Roads clearly increased risk of death for wolves from hunting and trapping and contributed to unsustainable rates of harvest. Wildlife managers should consider effects of roads and other habitat features on harvest of wolves when developing harvest recommendations. They should expect substantial illegal harvest where wolf habitat is accessible to humans. Moreover, high rates of mortality of nonresident wolves exposed to legal and illegal harvest may reduce or delay successful dispersal, potentially affecting linkages between small disjunct wolf populations or population segments. We conclude that a combination of conservative harvest regulations and large roadless reserves likely are the most effective measures for conserving wolves where risks from human-caused mortality are high.

Habitat reserves are a common strategy used to ensure viability of wildlife populations and communities. The efficacy of reserves, however, is rarely empirically evaluated. We examined the likelihood that small (650 ha), isolated habitat reserves composed of old-growth Sitka spruce ( Picea sitchensis )–western hemlock ( Tsuga heterophylla ) rain forest (upland-OG) and mixed-conifer peatlands (peatland-MC) would sustain populations of northern flying squirrels ( Glaucomys sabrinus ) in the absence of immigration or emigration within the Tongass National Forest in Southeast Alaska. We used demographic data obtained from a study of flying squirrels on Prince of Wales Island in Southeast Alaska and litter size from flying squirrels in similar habitat to estimate per capita rate of increase ( r ) of flying squirrels in upland-OG ( r = 0.14, SD = 0.42) and peatland-MC habitats ( r = 0.01, SD = 0.39). Our results indicated that peatland-MC habitat was unlikely to sustain populations and that viability of flying squirrel populations in small habitat reserves largely depended on the upland-OG forest component. We subsequently estimated time to extinction ( T N ) based on r , its variance ( v ), and the potential population ceiling ( K ). We used T N to calculate the probabilities ( P t ) that squirrel populations would persist in small reserves containing 100%, 50%, and 25% upland-OG habitat for 25, 50, and 100 years. In each scenario, we calculated T N and P t for 2 levels of v . For the best-case scenario (100% upland-OG forest, lowest variance, t = 25 years), T N was 507 years and P t was 0.95. For the worst-case scenario (25% upland-OG forest, highest variance, t = 100 years), T N was 237 years and P t was 0.66. Minimum patch size of upland-OG forest required for a high probability ( P t = 0.95) of sustaining a flying squirrel population in isolation with relatively low demographic variability ( v = 0.34) for 25, 50, or 100 years was 578, 5077, and 78,935 ha, respectively. We concluded that it was unlikely that small isolated habitat reserves could sustain populations of flying squirrels for >25 years in the absence of immigration. Consequently, dispersal among small reserves is critical to ensure that they function to support metapopulations of northern flying squirrels.

We investigated the influence of habitat use on the risk of death of Sitka black-tailed deer (Odocoileus hemionus sitkensis) on Heceta Island in Southeast Alaska, USA. A mosaic of even and uneven-aged forests covered much of the island and provided a model setting in which to assess relationships between habitat use and mortality of deer. We radiocollared and monitored 51 adult females, 11 adult males, and 19 young of the year. We compared risk of death with habitat composition, habitat distribution, topography, distances to features such as roads, and functional habitat characteristics such as seasonal forage biomass within 50-, 500-, and 1,000-m circular buffers around relocations of deer. Those buffers encompassed habitats used at scales of radio-locations, home ranges, and landscapes. We addressed hypotheses that related habitat composition and distribution to risk of death from malnutrition, predation, and hunting. Predation by wolves (Canis lupus) and malnutrition were the principal causes ...

Relatively little genetic variation has been uncovered in surveys across North American wolf populations. Pacific Northwest coastal wolves, in particular, have never been analysed. With an emphasis on coastal Alaska wolf populations, variation at 11 microsatellite loci was assessed. Coastal wolf populations were distinctive from continental wolves and high levels of diversity were found within this isolated and relatively small geographical region. Significant genetic structure within southeast Alaska relative to other populations in the Pacific Northwest, and lack of significant correlation between genetic and geographical distances suggest that differentiation of southeast Alaska wolves may be caused by barriers to gene flow, rather than isolation by distance. Morphological research also suggests that coastal wolves differ from continental populations. A series of studies of other mammals in the region also has uncovered distinctive evolutionary histories and high levels of endemism along the Pacific coast. Divergence of these coastal wolves is consistent with the unique phylogeographical history of the biota of this region and re-emphasizes the need for continued exploration of this biota to lay a framework for thoughtful management of southeast Alaska.

Relatively little genetic variation has been uncovered in surveys across North American wolf populations. Pacific Northwest coastal wolves, in particular, have never been analysed. With an emphasis on coastal Alaska wolf populations, variation at 11 microsatellite loci was assessed. Coastal wolf populations were distinctive from continental wolves and high levels of diversity were found within this isolated and relatively small geographical region. Significant genetic structure within southeast Alaska relative to other populations in the Pacific Northwest, and lack of significant correlation between genetic and geographical distances suggest that differentiation of southeast Alaska wolves may be caused by barriers to gene flow, rather than isolation by distance. Morphological research also suggests that coastal wolves differ from continental populations. A series of studies of other mammals in the region also has uncovered distinctive evolutionary histories and high levels of endemism along the Pacific coast. Divergence of these coastal wolves is consistent with the unique phylogeographical history of the biota of this region and re-emphasizes the need for continued exploration of this biota to lay a framework for thoughtful management of southeast Alaska.

We studied home ranges, activities, and habitat use of 29 radio-collared coyotes (Canis latrans) representing 11 different social groups in the Champlain Valley of Vermont. Between July 1984 and December 1986, 1,870 radio locations were obtained. Home ranges averaged 18.7 ? 4.6 (SE) km2 and 17.1 ? 3.2 km2 for adult males and females, respectively. All members of individual family groups shared the same home range. Home ranges were smaller during the pup-rearing period (15 Apr-15 Jul) than at other times of the year. Home ranges of adjacent social groups showed limited overlap, but smaller core activity areas were mutually exclusive. Study animals preferred hardwood forests during winter and spring, and farmland during summer and fall. J. WILDL. MANAGE. 55(3):433-441 In the last 50 years, coyotes have expanded their range east into northern New England, Quebec, and the maritime provinces of Canada (Richens and Hugie 1974). The first sightings of coyotes in Vermont were recorded in the 1940's (Pringle 1960), and they are now common throughout the state. The rapid increase in the coyote population in the Northeast is of ecological and management interest because of the impact these animals may have on livestock, indigenous prey species, and competing predators (Todd 1985, Litvaitis and Harrison 1989). Previous studies of coyotes in the Northeast have been conducted primarily in heavily forested habitats (Messier and Barrette 1982, Harrison and Gilbert 1985, Major and Sherburne 1987). No comprehensive eastern coyote research has been reported from a farming region, This content downloaded on Wed, 12 Dec 2012 22:50:46 PM All use subject to JSTOR Terms and Conditions 434 COYOTES IN VERMONT * Person and Hirth J. Wildl. Manage. 55(3):1991 although most farming is livestock-oriented and has high potential for conflict with coyotes. Furthermore, little information exists concerning coyote ecology in semi-rural residential areas where potential for human conflict with coyotes is also high. The objectives of our study were to examine home ranges and habitat use of coyotes in an agricultural region of Vermont and to compare these results with studies of eastern coyotes in forested environments. Because portions of our study area included habitat in transition from rural to urban, we examined coyote activities in these areas as well. This descriptive study is intended to provide baseline information prior to hypothesis-testing research on the interaction of coyotes and white-tailed deer (Odocoileus virginianus) in both agricultural and forested habitat. Our research was funded by Vermont Department of Fish and Wildlife through Federal Aid in Wildlife Restoration Project W-45-R-5. We are grateful to B. W. Day, Jr. and J. J. DiStefano of that agency for their support and encouragement throughout our work. Woodstream Corporation donated "Softcatch"? traps. D. E. Capen and G. J. Badger provided valuable advice on data analysis. S. J. Williamson, E. B. Soper, K. G. Timothy, and especially R. Hoffman and M. A. Ingle assisted in trapping and radiotracking. We are grateful to D. E. Capen, S. DeStefano, J. J. DiStefano, D. J. Harrison, M. A. Ingle, and A. W. Todd for reviewing earlier versions of this manuscript. Finally, we thank the many farmers who gave us permission to trap on their land.