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Full-Text Articles in Medicine and Health Sciences
Stress And Reproductive Hormones Reflect Inter-Specific Social And Nutritional Conditions Mediated By Resource Availability In A Bear–Salmon System, Heather M. Bryan, Chris T. Darimont, Paul C. Paquet, Katherine E. Wynne-Edwards, Judit E. G. Smits
Stress And Reproductive Hormones Reflect Inter-Specific Social And Nutritional Conditions Mediated By Resource Availability In A Bear–Salmon System, Heather M. Bryan, Chris T. Darimont, Paul C. Paquet, Katherine E. Wynne-Edwards, Judit E. G. Smits
Physiology Collection
Food availability can influence the nutritional and social dynamics within and among species. Our investigation focused on grizzly and black bears in coastal British Columbia, Canada, where recent and dramatic declines in their primary prey (salmon) raise concerns about potentially negative effects on bear physiology. We examined how salmon availability relates to stress and reproductive hormones in coastal grizzly (n = 69) and black bears (n = 68) using cortisol and testosterone. In hair samples from genotyped individuals, we quantified salmon consumption using stable isotope analysis and hormone levels by enzyme immunoassay. To estimate the salmon biomass available to each …
Spatial Analysis Of Factors Influencing Long-Term Stress In The Grizzly Bear (Ursus Arctos) Population Of Alberta, Canada, Mathieu Bourbonnais, Trisalyn Nelson, Mark Cattet, Chris T. Darimont, Gordon Stenhouse
Spatial Analysis Of Factors Influencing Long-Term Stress In The Grizzly Bear (Ursus Arctos) Population Of Alberta, Canada, Mathieu Bourbonnais, Trisalyn Nelson, Mark Cattet, Chris T. Darimont, Gordon Stenhouse
Physiology Collection
Non-invasive measures for assessing long-term stress in free ranging mammals are an increasingly important approach for understanding physiological responses to landscape conditions. Using a spatially and temporally expansive dataset of hair cortisol concentrations (HCC) generated from a threatened grizzly bear (Ursus arctos) population in Alberta, Canada, we quantified how variables representing habitat conditions and anthropogenic disturbance impact long-term stress in grizzly bears. We characterized spatial variability in male and female HCC point data using kernel density estimation and quantified variable influence on spatial patterns of male and female HCC stress surfaces using random forests. Separate models were developed for regions …