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1.
Ecol Evol ; 13(9): e10464, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37720065

RESUMO

Outdoor recreation is widespread, with uncertain effects on wildlife. The human shield hypothesis (HSH) suggests that recreation could have differential effects on predators and prey, with predator avoidance of humans creating a spatial refuge 'shielding' prey from people. The generality of the HSH remains to be tested across larger scales, wherein human shielding may prove generalizable, or diminish with variability in ecological contexts. We combined data from 446 camera traps and 79,279 sampling days across 10 landscapes spanning 15,840 km2 in western Canada. We used hierarchical models to quantify the influence of recreation and landscape disturbance (roads, logging) on ungulate prey (moose, mule deer and elk) and carnivore (wolf, grizzly bear, cougar and black bear) site use. We found limited support for the HSH and strong responses to recreation at local but not larger spatial scales. Only mule deer showed positive but weak landscape-level responses to recreation. Elk were positively associated with local recreation while moose and mule deer responses were negative, contrary to HSH predictions. Mule deer showed a more complex interaction between recreation and land-use disturbance, with more negative responses to recreation at lower road density or higher logged areas. Contrary to HSH predictions, carnivores did not avoid recreation and grizzly bear site use was positively associated. We also tested the effects of roads and logging on temporal activity overlap between mule deer and recreation, expecting deer to minimize interaction with humans by partitioning time in areas subject to more habitat disturbance. However, temporal overlap between people and deer increased with road density. Our findings highlight the complex ecological patterns that emerge at macroecological scales. There is a need for expanded monitoring of human and wildlife use of recreation areas, particularly multi-scale and -species approaches to studying the interacting effects of recreation and land-use change on wildlife.

2.
Ecol Evol ; 6(18): 6435-6451, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27777720

RESUMO

Quantifying the relative influence of multiple mechanisms driving recent range expansion of non-native species is essential for predicting future changes and for informing adaptation and management plans to protect native species. White-tailed deer (Odocoileus virginianus) have been expanding their range into the North American boreal forest over the last half of the 20th century. This has already altered predator-prey dynamics in Alberta, Canada, where the distribution likely reaches the northern extent of its continuous range. Although current white-tailed deer distribution is explained by both climate and human land use, the influence each factor had on the observed range expansion would depend on the spatial and temporal pattern of these changes. Our objective was to quantify the relative importance of land use and climate change as drivers of white-tailed deer range expansion and to predict decadal changes in white-tailed deer distribution in northern Alberta for the first half of the 21st century. An existing species distribution model was used to predict past decadal distributions of white-tailed deer which were validated using independent data. The effects of climate and land use change were isolated by comparing predictions under theoretical "no-change between decades" scenarios, for each factor, to predictions under observed climate and land use change. Climate changes led to more than 88%, by area, of the increases in probability of white-tailed deer presence across all decades. The distribution is predicted to extend 100 km further north across the northeastern Alberta boreal forest as climate continues to change over the first half of the 21st century.

3.
J Interpers Violence ; 29(13): 2355-2377, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24518666

RESUMO

While there is a large body of research on the effects of being a direct target of workplace aggression, there is far less research on the vicarious experience of aggression at work, despite the fact that more people experience workplace aggression vicariously (i.e., observe it or hear about it) than they do directly. In this study, we develop and test a model of the effects of direct and vicarious exposure to aggression that is directed at employees by customers. Structural equation modeling provided support for the proposed model, in which direct and vicarious workplace aggression influences the perceived risk of future workplace aggression, which in turn affects organizational attachment (affective commitment and turnover intentions) and individual well-being (psychological and physical). Conceptual research and policy implications are discussed.

4.
PLoS One ; 7(2): e31672, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363702

RESUMO

Habitat protection has been identified as an important strategy for the conservation of woodland caribou (Rangifer tarandus). However, because of the economic opportunity costs associated with protection it is unlikely that all caribou ranges can be protected in their entirety. We used an optimization approach to identify reserve designs for caribou in Alberta, Canada, across a range of potential protection targets. Our designs minimized costs as well as three demographic risk factors: current industrial footprint, presence of white-tailed deer (Odocoileus virginianus), and climate change. We found that, using optimization, 60% of current caribou range can be protected (including 17% in existing parks) while maintaining access to over 98% of the value of resources on public lands. The trade-off between minimizing cost and minimizing demographic risk factors was minimal because the spatial distributions of cost and risk were similar. The prospects for protection are much reduced if protection is directed towards the herds that are most at risk of near-term extirpation.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Rena/fisiologia , Alberta , Animais , Conservação dos Recursos Naturais/economia , Geografia , Modelos Teóricos , Dinâmica Populacional
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