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Encounters between animals occur when animals are close in space and time. Encounters are important in many ecological processes including sociality, predation and disease transmission. Despite this, there is little theory regarding the spatial distribution of encounters and no formal framework to relate environmental characteristics to encounters. The probability of encounter could be estimated with resource selection functions (RSFs) by comparing locations where encounters occurred to available locations where they may have occurred, but this estimate is complicated by the hierarchical nature of habitat selection.We developed a method to relate resources to the relative probability of encounter based on a scale‐integrated habitat selection framework. This framework integrates habitat selection at multiple scales to obtain an appropriate estimate of availability for encounters. Using this approach, we related encounter probabilities to landscape resources. The RSFs describe habitat associations at four scales, home ranges within the study area, areas of overlap within home ranges, locations within areas of overlap, and encounters compared to other locations, which can be combined into a single scale‐integrated RSF. We apply this method to intraspecific encounter data from two species: white‐tailed deer (Odocoileus virginianus) and elk (Cervus elaphus) and interspecific encounter data from a two‐species system of caribou (Rangifer tarandus) and coyote (Canis latrans).Our method produced scale‐integrated RSFs that represented the relative probability of encounter. The predicted spatial distribution of encounters obtained based on this scale‐integrated approach produced distributions that more accurately predicted novel encounters than a naïve approach or any individual scale alone.Our results highlight the importance of accounting for the conditional nature of habitat selection in estimating the habitat associations of animal encounters as opposed to 'naïve' comparisons of encounter locations with general availability. This method has direct relevance for testing hypotheses about the relationship between habitat and social or predator–prey behaviour and generating spatial predictions of encounters. Such spatial predictions may be vital for understanding the distribution of encounters driving disease transmission, predation rates and other population and community‐level processes. [ABSTRACT FROM AUTHOR]

Background: Spatial behavior, including home-ranging behaviors, habitat selection, and movement, can be extremely informative in estimating how animals respond to landscape heterogeneity. Responses in these spatial behaviors to features such as human land modification and resources can highlight a species' spatial strategy to maximize fitness and minimize mortality. These strategies can vary on spatial, temporal, and individual scales, and the combination of behaviors on these scales can lead to very different strategies among species. Methods: Harnessing the variation present at these scales, we characterized how species may respond to stimuli in their environments ranging from broad- to fine-scale spatial responses to human modification in their environment. Using 15 bobcat-years and 31 coyote-years of GPS data from individuals inhabiting a landscape encompassing a range of human land modification, we evaluated the complexity of both species' responses to human modification on the landscape through their home range size, habitat selection, and functional response behaviors, accounting for annual, seasonal, and diel variation. Results: Bobcats and coyotes used different strategies in response to human modification in their home ranges, with bobcats broadly expanding their home range with increases in human modification and displaying temporal consistency in functional response in habitat selection across both season and time of day. Meanwhile, coyotes did not expand their home ranges with increased human modification, but instead demonstrated fine-scale responses to human modification with habitat selection strategies that sometimes varied by time of day and season, paired with functional responses in selection behaviors. Conclusions: These differences in response to habitat, resources, and human modification between the two species highlighted the variation in spatial behaviors animals can use to exist in anthropogenic environments. Categorizing animal spatial behavior based on these spatiotemporal responses and individual variation can help in predicting how a species will respond to future change based on their current spatial behavior. [ABSTRACT FROM AUTHOR]

SNAPSHOT USA is a multicontributor, long‐term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application (https://www.snapshot-usa.org/). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Here we present the SNAPSHOT USA 2021 dataset, the third national camera trap survey across the US. Data were collected across 109 camera trap arrays and included 1711 camera sites. The total effort equaled 71,519 camera trap nights and resulted in 172,507 sequences of animal observations. Sampling effort varied among camera trap arrays, with a minimum of 126 camera trap nights, a maximum of 3355 nights, a median 546 nights, and a mean 656 ± 431 nights. This third dataset comprises 51 camera trap arrays that were surveyed during 2019, 2020, and 2021, along with 71 camera trap arrays that were surveyed in 2020 and 2021. All raw data and accompanying metadata are stored on Wildlife Insights (https://www.wildlifeinsights.org/), and are publicly available upon acceptance of the data papers. SNAPSHOT USA aims to sample multiple ecoregions in the United States with adequate representation of each ecoregion according to its relative size. Currently, the relative density of camera trap arrays varies by an order of magnitude for the various ecoregions (0.22–5.9 arrays per 100,000 km2), emphasizing the need to increase sampling effort by further recruiting and retaining contributors. There are no copyright restrictions on these data. We request that authors cite this paper when using these data, or a subset of these data, for publication. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the US Government. [ABSTRACT FROM AUTHOR]

Raccoon rabies virus (RRV) has been managed using multiple vaccination strategies, including oral rabies vaccination and trap-vaccinate-release (TVR). Identifying a rabies vaccination strategy for an area is a nontrivial task. Vaccination strategies differ in the amount of effort and monetary costs required to achieve a particular level of vaccine seroprevalence (efficiency). Simulating host movement relative to different vaccination strategies in silico can provide a useful tool for exploring the efficiency of different vaccination strategies. We refined a previously developed individual-based model of raccoon movement to evaluate vaccination strategies for urban Hamilton, Ontario, Canada. We combined different oral rabies vaccination baiting (hand baiting, helicopter, and bait stations) with TVR strategies and used GPS data to parameterize and simulate raccoon movement in Hamilton. We developed a total of 560 vaccination strategies, in consultation with the Ontario Ministry of Natural Resources and Forestry, for RRV control in Hamilton. We documented the monetary costs of each vaccination strategy and estimated the population seroprevalence. Intervention costs and seroprevalence estimates were used to calculate the efficiency of each strategy to meet targets set for the purpose of RRV control. Estimated seroprevalence across different strategies varied widely, ranging from less than 5% to more than 70%. Increasing bait densities (distributed using by hand or helicopter) led to negligible increase in seroprevalence. Helicopter baiting was the most efficient and TVR was the least efficient, but helicopter-based strategies led to lower levels of seroprevalence (6–12%) than did TVR-based strategies (17–70%). Our simulations indicated that a mixed strategy including at least some TVR may be the most efficient strategy for a local urban RRV control program when seroprevalence levels >30% may be required. Our simulations provide information regarding the efficiency of different vaccination strategies for raccoon populations, to guide local RRV control in urban settings. [ABSTRACT FROM AUTHOR]

Background: Movement is a core mechanism through which animals interact with their environment. GPS telemetry is a popular approach used to investigate animal movement, providing access to both the spatial and temporal behavioral patterns exhibited by an individual or population. However, while some species are easily tracked through traditional GPS attachment methods (such as GPS collars or backpacks), other species such as the North American beaver (Castor canadensis) present unique challenges given their fusiform shape and tapered neck. Results: We tested three different GPS transmitter attachment methods (tail-mounted, lower back glued-on, and upper back glued-on) for beavers over two seasons to determine which treatment was most effective in terms of retention time (RT, total number of days a transmitter remains attached) and GPS fix success rate (FSR, % of successful fixes vs. attempted) and investigated to what degree various factors (season, sex, and age class) affected these results. We then evaluated whether the data collected were sufficient for identifying home-ranging behavior (when an individual begins to display restricted space use and range residency). We found transmitters attached to the lower back during the fall to be the top performing treatment, having a similar mean FSR (51.59%) to upper back attachments in fall, but a significantly greater average RT (42.8 days). Of the 23 individuals included in the home-ranging behavior analysis, all but two had sufficient data for identifying home-ranging behavior. Conclusions: Our tests show that glued-on GPS tags can provide up to 2 months of fine-scale relocation data in a safe and effective manner. This allows the opportunity to answer novel questions regarding movement patterns of beavers and other semi-aquatic mammals. [ABSTRACT FROM AUTHOR]

Generalist predators typically have broad diets, but their diets may become constrained when one species of prey becomes disproportionately available. Yet there is poor understanding regarding whether generalist predators exhibit stereotypic relationships with pulsed prey resources. We used telemetry data from 959 woodland caribou (Rangifer tarandus caribou (Gmelin, 1788); 146 adult females, 813 calves), 61 coyotes (Canis latrans Say, 1823), and 55 black bears (Ursus americanus Pallas, 1780) to investigate how two generalist predators interacted with caribou neonates on the island of Newfoundland. We examined the similarity of patterns of habitat use between caribou and their predators across time and related this similarity to interspecific spatiotemporal co-occurrence and mortality risk for caribou neonates. The similarity in habitat use between coyotes and caribou mirrored variation in juvenile hazard risk, but had weak association with actual co-occurrence with caribou. Bears and caribou exhibited less similarity in habitat use during the calving season than coyotes and caribou. The relationship between habitat use of bear and caribou did not correspond with either co-occurrence patterns or overall risk for caribou neonates. Our work illustrates how risk for a prey species can be shaped differently based upon differences between the behavioural strategies of generalist predator species. Key words: black bear, Ursus americanus, woodland caribou, Rangifer tarandus caribou, coyote, Canis latrans, neonates, Newfoundland, predator-prey interactions, specialist-generalist predators. Les predateurs generalistes presentent typiquement des regimes alimentaires varies, mais ces derniers peuvent devenir restreints quand la disponibilite d'une espece de proie devient disproportionnement grande. Cela dit, la possibilite qu'il existe des relations stereotypees de predateurs avec des ressources de proies pulsees est mal comprise. Nous avons utilise des donnees de telemetrie sur 959 caribous des bois (Rangifer tarandus caribou (Gmelin, 1788), 146 femelles adultes, 813 veaux), 61 coyotes (Canis latrans Say, 1823) et 55 ours noirs (Ursus americanus Pallas, 1780) pour etudier les interactions de deux predateurs generalistes avec des caribous nouveau-nes dans Pile de Terre-Neuve. Nous avons examine la similitude des motifs d'utilisation de l'habitat entre les caribous et leurs predateurs dans le temps et relie cette similitude a la cooccurrence spatiotemporelle interspecifique et au risque de mortalite pour les caribous nouveau-nes. La similitude de l'utilisation de l'habitat entre les coyotes et les caribous reflete les variations du risque de dangers pour les jeunes, mais n'est que faiblement associee a la cooccurrence avec les caribous. Les ours et les caribous presentent une moins grande similitude sur le plan de l'utilisation de l'habitat durant la saison de mise bas que les coyotes et les caribous. La relation entre l'utilisation de l'habitat par les ours et les caribous ne correspond pas avec les motifs de cooccurrence, ni avec le risque global pour les caribous nouveau-nes. Nos travaux illustrent les differentes incidences sur les risques pour une espece de proie de differentes strategies comportementales d'especes de predateurs generalistes. [Traduit par la Redaction] Mots-cles: ours noir, Ursus americanus, caribou des bois, Rangifer tarandus caribou, coyote, Canis latrans, nouveau-nes, Terre-Neuve, interactions predateur-proie, predateurs specialistes-generalistes., Introduction Predation is a key force shaping most ecosystems (Getz 2011) and one of the key drivers of animal evolution (Roff 1996). Predator-prey interactions are generally conceptualized as complex games [...]

Many populations of caribou (Rangifer tarandus (L., 1758)) across North America, including Newfoundland, are in a state of decline. This phenomenon may reflect continental-scale changes in either the extrinsic or the intrinsic factors affecting caribou abundance. We hypothesized that caribou decline reflected marked resource limitation and predicted that fluctuations should correspond to time-delayed density dependence associated with a decline in range quality and decadal trends in winter severity. By conducting time-series analysis using 12 populations and evaluating correlations between caribou abundance and trends in (i) vegetation available at calving (normalized difference vegetation index, NDVI), (ii) winter weather severity (index of North Atlantic Oscillation, NAO), and (iii) caribou morphometrics, we observed strong evidence of density dependence in population dynamics (i.e., a negative relationship between caribou population size and caribou morphometrics). Caribou population trajectories were time-delayed relative to winter severity, but not relative to calving-ground greenness. These island-wide correlations could not be traced to dispersal between herds, which appears rare at least for adult females. Our results suggest that trends in winter severity may synchronize broad-scale changes in caribou abundance that are driven by time-delayed density dependence, although it remains possible that calving-ground deterioration also may contribute to population limitation in Newfoundland. Our findings provide the basis for additional research into density dependence and caribou population decline. Key words: density dependence, climate influence, synchrony, predation, caribou, Rangifer tarandus. Plusieurs populations de caribou (Rangifer tarandus (L., 1758)) en Amerique du Nord, dont celles de Terre-Neuve, sont en declin. Ce phenomene peut refleter des changements continentaux dans les facteurs extrinseques ou intrinseques affectant leur abondance. Nous supposons que le declin observe reflete un cycle naturel, et predisons que les fluctuations devraient correspondre al des effets densite-dependants differes dans le temps, associes a la qualite de l'habitat et a la severite des hivers. Afin de mieux comprendre les raisons expliquant les tendances observees a Terre-Neuve, nous avons conduit des analyses temporelles en utilisant 12 populations et nous avons evalue les correlations entre l'abondance des caribous et (i) la vegetation disponible durant la mise-bas (l'indice d'activite vegetale, NDVI), (ii) la severite de l'hiver (l'indice de l'oscillation nord atlantique, NAO) et (iii) les mesures morphometriques. Nous avons observe une forte correlation entre la taille des populations et les effets densitedependants. La trajectoire des populations de caribou etait aussi correlee, mais differee avec la severite des hivers, mais pas avec la qualite des aires de mise-bas. Ces correlations n'etaient pas liees a la dispersion des individus entre les troupeaux, qui semblait rare, du moins chez les femelles. Nos resultats suggerent que les tendances dans la severite des hivers pourraient synchroniser a grande echelle les changements d'abondance chez le caribou, bien qu'il semble possible que la degradation de l'habitat puisse contribuer a la limitation des populations. Mots-cles: densite dependence, influence du climat, synchronie, predation, caribou, Rangifer tarandus., Introduction Fluctuations in animal population density can be driven by a range of factors, including endogenous (i.e., density-dependent) factors linked to predation, competition, and parasitism (Kendall et al. 1999; Turchin [...]

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