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Local and Landscape‐Level Environmental Conditions Drive Habitat Selection Across Terrestrial Mammal SpeciesNARA Subscribed
Aim Animal movements are a fundamental process affecting communities and ecosystems. Quantifying habitat selection across species and habitats is key for understanding how animals respond to environmental change. Currently, we lack comparative studies that examine how habitat selection varies across species traits and landscapes. We aim to quantify global patterns of habitat selection to help understand the fundamental drivers...
Global Change Affects Large Herbivore Forage Biomass Through Gradual Successional Shifts and Abrupt DisturbancesNARA Subscribed
Forage availability is a key factor regulating large herbivore populations. Global changes in land use and climate may affect the spatiotemporal distribution of forage across the ranges of large herbivores, especially in mountain ecosystems. We test two synergistic hypotheses for how landscape and climate changes from 2001 to 2023 have affected forb and graminoid biomass at the peak of the growing season within and across ecor...
SNAPSHOT USA 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multicontributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of specie...
Animals within social groups respond to costs and benefits of sociality by adjusting the proportion of time they spend in close proximity to other individuals in the group (cohesion). Variation in cohesion between individuals, in turn, shapes important group‐level processes such as subgroup formation and fission–fusion dynamics. Although critical to animal sociality, a comprehensive understanding of the factors influencing coh...
Genetic mechanisms determining habitat selection and specialization of individuals within species have been hypothesized, but not tested at the appropriate individual level in nature. In this work, we analyzed habitat selection for 139 GPS‐collared caribou belonging to 3 declining ecotypes sampled throughout Northwestern Canada. We used Resource Selection Functions comparing resources at used and available locations. We found...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Migration is a tactic used across taxa to access resources in temporally heterogenous landscapes. Populations that migrate can attain higher abundances because such movements allow access to higher quality resources, or reduction in predation risk resulting in increased fitness. However, most migratory species occur in partially migratory populations, a mix of migratory and non‐migratory individuals. It is thought that the por...
Human activity and land use change impact every landscape on Earth, driving declines in many animal species while benefiting others. Species ecological and life history traits may predict success in human‐dominated landscapes such that only species with “winning” combinations of traits will persist in disturbed environments. However, this link between species traits and successful coexistence with humans remains obscured by th...
Genomics, environment and balancing selection in behaviourally bimodal populations: The caribou caseNARA Subscribed
Selection forces that favour different phenotypes in different environments can change frequencies of genes between populations along environmental clines. Clines are also compatible with balancing forces, such as negative frequency‐dependent selection (NFDS), which maintains phenotypic polymorphisms within populations. For example, NFDS is hypothesized to maintain partial migration, a dimorphic behavioural trait prominent in...
Sampling scales define occupancy and underlying occupancy–abundance relationships in animalsNARA Subscribed
Occupancy–abundance ( OA ) relationships are a foundational ecological phenomenon and field of study, and occupancy models are increasingly used to track population trends and understand ecological interactions. However, these two fields of ecological inquiry remain largely isolated, despite growing appreciation of the importance of integration. For example, using occupancy models to infer trends in abundance is predicated on...
Variation in stability of elk and red deer populations with abiotic and biotic factors at the species‐distribution scaleNARA Subscribed
Stability in population dynamics is an emergent property of the interaction between direct and delayed density dependence, the strengths of which vary with environmental covariates. Analysis of variation across populations in the strength of direct and delayed density dependence can reveal variation in stability properties of populations at the species level. We examined the stability properties of 22 elk/red deer populations...
Evaluating multispecies landscape connectivity in a threatened tropical mammal communityNARA Subscribed
Habitat corridors are important tools for maintaining connectivity in increasingly fragmented landscapes, but generally they have been considered in single‐species approaches. Corridors intended to facilitate the movement of multiple species could increase persistence of entire communities, but at the likely cost of being less efficient for any given species than a corridor intended specifically for that species. There have be...
Reconstruction of caribou evolutionary history in Western North America and its implications for conservationNARA Subscribed
The role of Beringia as a refugium and route for trans‐continental exchange of fauna during glacial cycles of the past 2 million years are well documented; less apparent is its contribution as a significant reservoir of genetic diversity. Using mitochondrial DNA sequences and 14 microsatellite loci, we investigate the phylogeographic history of caribou ( Rangifer tarandus ) in western North America. Patterns of genetic diversi...
Maintenance of viable populations of many endangered species will require conservation action in perpetuity. Efforts to conserve these species are more likely to be successful if their reliance on conservation actions is assessed at the population level. Woodland caribou ( Rangifer tarandus caribou ) were extirpated recently from Banff National Park, Canada, and translocations of caribou to Banff and neighboring Jasper Nationa...
Generalized functional responses for species distributionsNARA Subscribed
Trade‐offs between predation risk and forage differ between migrant strategies in a migratory ungulateNARA Subscribed
Trade‐offs between predation risk and forage fundamentally drive resource selection by animals. Among migratory ungulates, trade‐offs can occur at large spatial scales through migration, which allows an “escape” from predation, but trade‐offs can also occur at finer spatial scales. Previous authors suggest that ungulates will avoid predation risk at the largest scale, although few studies have examined multi‐scale trade‐offs t...
Survival in the Rockies of an endangered hybrid swarm from diverged caribou ( Rangifer tarandus ) lineagesNARA Subscribed
In North America, caribou ( Rangifer tarandus ) experienced diversification in separate refugia before the last glacial maximum. Geographical isolation produced the barren‐ground caribou ( Rangifer tarandus groenlandicus ) with its distinctive migratory habits, and the woodland caribou ( Rangifer tarandus caribou ), which has sedentary behaviour and is now in danger of extinction. Herein we report on the phylogenetics, populat...