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A cross‐site comparison reveals limited geographic variation in risk avoidance of snowshoe haresNARA Subscribed
Predation risk induces a myriad of behavioral antipredator responses of prey. However, different antipredator behaviors exhibit different degrees of flexibility within a single prey species. Moreover, how predator species composition and traits interact with the flexibility of particular antipredator behaviors to determine spatiotemporal activity patterns of prey remains unknown. We examined geographic variation in multiple be...
Spatial confinement to a home range is theorized to be a more energetically efficient method of acquiring resources than random searching due to spatial memory. Intraspecific studies that have compared home range size at different population densities have found that home ranges shrink as population density increases. This negative trend could be due to increased conspecific competition via population density increase or due t...
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...
Noradrenergic regulation of cue-guided decision making and impulsivity is doubly dissociable across frontal brain regionsNARA Subscribed
Rationale Win-paired stimuli can promote risk taking in experimental gambling paradigms in both rats and humans. We previously demonstrated that atomoxetine, a noradrenaline reuptake inhibitor, and guanfacine, a selective α2A adrenergic receptor agonist, reduced risk taking on the cued rat gambling task (crGT), a rodent assay of risky choice in which wins are accompanied by salient cues. Both compounds also decreased impulsive...
Seasonal and diel patterns in Pacific white‐sided dolphin ( Lagenorhynchus obliquidens ) pulsed calls near Barkley CanyonNARA Subscribed
Evaluation of temporal patterns in offshore marine mammal activity through visual data collection can be impaired by light and weather conditions and the cost of ship time. The conditions‐independence and cost‐efficacy of acoustic data collection make it popular for researching the temporal patterns of wild dolphins. However, Pacific white‐sided dolphins (PWSDs) north of Southern California remain under‐researched. This study...
Evaluating potential changes to the US Chukchi Sea bottom trawl survey design via simulation testingOA Marine
The US Chukchi Sea consists of the waters off the northwest of Alaska and is a naturally dynamic ice-driven ecosystem. The impacts from climate change are affecting the Arctic marine ecosystem as well as the coastal communities that rely on healthy marine ecosystems. In anticipation of increased ecosystem monitoring in the area, there is an opportunity to evaluate improved sampling designs for future ecological monitoring of t...
Coat color mismatch improves survival of a keystone boreal herbivore: Energetic advantages exceed lost camouflageNARA Subscribed
Climate warming is causing asynchronies between animal phenology and environments. Mismatched traits, such as coat color change mismatched with snow, can decrease survival. However, coat change does not serve a singular adaptive benefit of camouflage, and alternate coat change functions may confer advantages that supersede mismatch costs. We found that mismatch reduced, rather than increased, autumn mortality risk of snowshoe...
Balancing food acquisition and predation risk drives demographic changes in snowshoe hare population cyclesNARA Subscribed
Snowshoe hare cycles are one of the most prominent phenomena in ecology. Experimental studies point to predation as the dominant driving factor, but previous experiments combining food supplementation and predator removal produced unexplained multiplicative effects on density. We examined the potential interactive effects of food limitation and predation in causing hare cycles using an individual‐based food‐supplementation exp...
Food availability and long‐term predation risk interactively affect antipredator responseNARA Subscribed
Food availability and temporal variation in predation risk are both important determinants of the magnitude of antipredator responses, but their effects have rarely been examined simultaneously, particularly in wild prey. Here, we determine how food availability and long‐term predation risk affect antipredator responses to acute predation risk by monitoring the foraging response of free‐ranging snowshoe hares ( Lepus americanu...
Spatio‐temporal analyses of marine predator diets from data‐rich and data‐limited systemsNARA Subscribed
Accounting for variation in prey mortality and predator metabolic potential arising from spatial variation in consumption is an important task in ecology and resource management. However, there is no statistical method for processing stomach content data that accounts for fine‐scale spatio‐temporal structure while expanding individual stomach samples to population‐level estimates of predation. Therefore, we developed an approa...
Demography of snowshoe hare population cyclesNARA Subscribed
Cyclic fluctuations in abundance exhibited by some mammalian populations in northern habitats (“population cycles”) are key processes in the functioning of many boreal and tundra ecosystems. Understanding population cycles, essentially demographic processes, necessitates discerning the demographic mechanisms that underlie numerical changes. Using mark–recapture data spanning five population cycles (1977–2017), we examined demo...
TRY plant trait database – enhanced coverage and open accessNARA Subscribed
Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodivers...
Background Studies that attempt to measure shifts in species distributions often consider a single species in isolation. However, understanding changes in spatial overlap between predators and their prey might provide deeper insight into how species redistribution affects food web dynamics. Predator–prey overlap metrics Here, we review a suite of 10 metrics [range overlap, area overlap, the local index of collocation (Pianka's...
Mantle electrical conductivity profile of Niger delta regionNARA Subscribed