Moose (Alces alces) have experienced considerable declines along the periphery of their range in the northeastern United States. In Vermont, the population declined 45% from 2010 to 2017 despite minimal hunter harvest and adequate habitat. Similarly, nearby populations recently experienced epizootics characterized by >50% mortality. Declines have largely been associated with the effects of winter ticks (Dermacentor albipictus), but uncertainty exists about the effects of environmental and other parasite‐related conditions on moose survival. We examined patterns of moose survival among a radio‐collared population (n = 127) in Vermont from 2017 to 2019. Our objectives were to estimate causes of mortality and model survival probability as a function of individual and landscape variables for calves (<1 yr) and adults (≥1 yr). Observed adult survival was 90% in 2017, 84% in 2018, and 86% in 2019, and winter calf survival was 60% in 2017, 50% in 2018, and 37% in 2019. Winter tick infestation was the primary cause of mortality (91% of calves, 25% of adults), and 32% of all mortalities had evidence of meningeal worm (Parelaphostrongylus tenuis). Other sources of mortality such as vehicles, harvest, predation, deep snow, and other parasitic infections were negligible. The best supported calf model included sex differences and negative effects of tick engorgement (%/week) and parasite level (roundworm and lungworm). The best supported adult model included the effect of cumulative tick engorgement (cumulative %/week), which negatively affected survival. Our results indicate that winter tick engorgement strongly affects survival, and is probably compounded by the presence of meningeal worm and other parasites. Reduced tick effects may be achieved by decreasing moose density through harvest and managing late winter habitat to minimize tick density. Management of white‐tailed deer (Odocoileus virginianus) density may also affect the transmission of meningeal worm. © 2021 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society.

The analysis of individual movement choices can be used to better understand population-level resource selection and inform management.

Natal dispersal in vagile species such as songbirds can shape a population's range and structure. Although effective conservation practices depend on knowledge of the scale and frequency of natal dispersal, these issues remain poorly understood because of methodological gaps. In this exploratory study, we assessed whether element signatures within natal feathers might be used to identify the geographic birth site of first-year breeders. We used two related techniques, inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma with optical emission spectrometry (ICP-AES), to quantify element levels in natal feather samples from 7 species at 27 sites across the eastern United States. The techniques differed in the manner in which elements were quantified and in their detection limits. Our goal was to determine whether element analyses of feathers could discriminate (1) different species within a site and (2) different sites within a species. Additionally, because spatial autocorrelation of element levels is needed for element analysis to be an effective tool in assessing natal dispersal, we also evaluated the spatial autocorrelation of ICP-AES samples at 18 sites across the eastern United States. Both ICP-MS and ICP-AES analyses separated species within a site with fairly high accuracy, though the discriminating elements varied with site. However, within a species, natal feather locations were not identified with high accuracy on the basis of feather elements. We were not able to determine whether there is spatial correlation among individual elements or a principal component analysis (PCA) score that described the elemental makeup of a feather. A kriging model was fit to the semivariogram of PCA scores to produce a base-map of element signatures across the eastern United States. This map was ineffective at predicting feather-element values at sample sites. Whether elemental analyses can identify natal dispersal distances requires further study. We suggest that future studies evaluate elements with ICP-MS methodologies on a single, box-nesting species that is sampled more intensively at smaller geographic scale, or on species that occur in very discrete populations. Additionally, this methodology should be evaluated in concert with stable-isotope analyses of feathers and, potentially, genetic analyses. Suivre la Dispersion chez les Oiseaux: Évaluer le Potentiel de Marqueurs Élémentaires La dispersion natale chez les espèces vagiles comme les passereaux peut modeler la portée et la structure d'une population. Bien que les pratiques de conservation efficaces dépendent des connaissances acquises sur l'échelle et la fréquence de la dispersion natale, ces questions demeurent peu comprises en raison de lacunes méthodologiques. Dans cette étude exploratoire, nous avons cherché à savoir si la signature des éléments contenus dans les plumes natales pourrait être utilisée afin d'identifier le site géographique de naissance des reproducteurs de première année. Nous avons utilisé deux techniques semblables, l'ICP-MS (inductively coupled plasma mass spectrometry) et l'ICP-AES (inductively coupled plasma with optical emission spectrometry), pour quantifier les niveaux d'éléments dans les plumes natales issues de 7 espèces dans 27 sites à travers l'est des États-Unis. Les techniques différaient dans la manière avec laquelle les éléments étaient quantifiés et leurs limites de détection. Notre but était de déterminer si les éléments analysés dans les plumes pouvaient discriminer (1) différentes espèces à l'intérieur d'un même site (2) différents sites à l'intérieur d'une même espèce. L'autocorrélation spatiale des niveaux d'éléments est nécessaire à leur analyse, et ce dans le but de constituer un outil efficace pour l'évaluation de la dispersion natale. Par conséquent, nous avons également évalué l'autocorrélation spatiale d'échantillons ICP-AES provenant de 18 sites à travers l'est des États-Unis. Les analyses ICP-MS et ICP-AES ont séparé les espèces à l'intérieur d'un même site avec une relativement bonne précision, bien que les éléments discriminants ont varié avec les sites. Néanmoins, pour une même espèce, la localisation des plumes natales n'a pas été identifiée avec une grande précision à partir des caractéristiques des éléments. Nous n'avons pas été capables de déterminer s'il y avait une corrélation spatiale parmi les éléments individuels ou un score d'analyse en composante principale (ACP) qui décrivaient l'assemblage des éléments dans une plume. Un modèle <> a été ajusté au semi-variogramme des scores d'APC afin de produire une carte de base des signatures d'éléments à travers l'est des États-Unis. Cette carte s'est avérée inefficace pour prédire les valeurs des éléments contenus dans les plumes aux sites d'échantillonnage. D'autres études seront nécessaires pour déterminer si les analyses d'éléments permettent d'identifier les distances de dispersion natale. Nous suggérons que des études futures puissent évaluer les éléments avec la méthodologie ICP-MS pour une seule espèce qui utilise des nichoirs et qui pourrait être échantillonnée plus...

Moose populations in the northeastern United States have declined over the past 15 years, primarily due to the impacts of winter ticks. Research efforts have focused on the effects of winter tick infestation on moose survival and reproduction, but stress and nutritional responses to ticks and other stressors remain understudied. We examined the influence of several environmental factors on moose calf stress hormone metabolite concentrations and nutritional restriction in Vermont, USA. We collected 407 fecal and 461 snow urine samples from 84 radio-collared moose calves in the winters of 2017–2019 (January–April) to measure fecal glucocorticoid metabolites (fGCM) concentrations and urea nitrogen:creatinine (UN:C) ratios. We used generalized mixed-effects models to evaluate the influence of individual condition, winter ticks, habitat, climate and human development on stress and nutrition in calf moose. We then used these physiological data to build generalized linear models to predict calf winter survival. Calf fGCM concentrations increased with nutritional restriction and snow depth during adult winter tick engorgement. Calf UN:C ratios increased in calves with lighter weights and higher tick loads in early winter. Calf UN:C ratios also increased in individuals with home ranges composed of little deciduous forests during adult winter tick engorgement. Our predictive models estimated that winter survival was negatively related to UN:C ratios and positively related to fGCM concentrations, particularly in early winter. By late March, as winter ticks are having their greatest toll and endogenous resources become depleted, we estimated a curvilinear relationship between fGCM concentrations and survival. Our results provide novel evidence linking moose calf stress and nutrition, a problematic parasite and challenging environment and winter survival. Our findings provide a baseline to support the development of non-invasive physiological monitoring for assessing environmental impacts on moose populations.