1
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Wilson AE, Michaud SA, Jackson AM, Stenhouse G, McClelland CJR, Coops NC, Janz DM. Protein biomarkers in serum as a conservation tool to assess reproduction: a case study on brown bears ( Ursus arctos). CONSERVATION PHYSIOLOGY 2021; 9:coab091. [PMID: 34888057 PMCID: PMC8651255 DOI: 10.1093/conphys/coab091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/26/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Monitoring the reproductive characteristics of a species can complement existing conservation strategies by understanding the mechanisms underlying demography. However, methodology to determine important aspects of female reproductive biology is often absent in monitoring programs for large mammals. Protein biomarkers may be a useful tool to detect physiological changes that are indicative of reproductive state. This study aimed to identify protein biomarkers of reproductive status in serum collected from free-ranging female brown bears (Ursus arctos) in Alberta, Canada, from 2001 to 2018. We hypothesized that the expression of proteins related to reproduction in addition to energetics and stress can be used to answer specific management-focused questions: (i) identify when a female is pregnant, (ii) detect if a female is lactating, (iii) determine age of sexual maturity (i.e. primiparity) and (iv) assess female fertility (i.e. reproduction rate). Furthermore, we investigated if silver spoon effects (favourable early life conditions provide fitness benefits through adulthood) could be determined using protein expression. A target panel of 19 proteins with established relationships to physiological function was measured by peptide-based analysis using liquid chromatography and multiple reaction monitoring mass spectrometry and their differential expression was evaluated using a Wilcoxon signed-rank test. We found biomarkers of pregnancy (apolipoprotein B-100 and afamin), lactation (apolipoprotein B-100 and alpha-2-macroglobulin) and sexual maturity (corticosteroid-binding globulin), but there were no statistically significant relationships with protein expression and fertility. The expression of proteins related to reproduction (afamin) and energetics (vitamin-D binding protein) was associated with the nutritional quality of the individual's present habitat rather than their early life habitat. This study highlights potential biomarkers of reproductive status and provides additional methods for monitoring physiological function in wildlife to inform conservation.
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Affiliation(s)
- Abbey E Wilson
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada
| | - Sarah A Michaud
- The University of Victoria Genome BC Proteomics Centre, 4464 Markham St #3101, Victoria, British Columbia V8Z 7X8, Canada
| | - Angela M Jackson
- The University of Victoria Genome BC Proteomics Centre, 4464 Markham St #3101, Victoria, British Columbia V8Z 7X8, Canada
| | - Gordon Stenhouse
- Grizzly Bear Program, fRI Research, 1176 Switzer Drive, Hinton, Alberta T7V 1V3, Canada
| | | | - Nicholas C Coops
- Department of Forest Resource Management, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - David M Janz
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada
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2
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Hantak MM, McLean BS, Li D, Guralnick RP. Mammalian body size is determined by interactions between climate, urbanization, and ecological traits. Commun Biol 2021; 4:972. [PMID: 34400755 PMCID: PMC8367959 DOI: 10.1038/s42003-021-02505-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 07/28/2021] [Indexed: 11/20/2022] Open
Abstract
Anthropogenically-driven climate warming is a hypothesized driver of animal body size reductions. Less understood are effects of other human-caused disturbances on body size, such as urbanization. We compiled 140,499 body size records of over 100 North American mammals to test how climate and human population density, a proxy for urbanization, and their interactions with species traits, impact body size. We tested three hypotheses of body size variation across urbanization gradients: urban heat island effects, habitat fragmentation, and resource availability. Our results demonstrate that both urbanization and temperature influence mammalian body size variation, most often leading to larger individuals, thus supporting the resource availability hypothesis. In addition, life history and other ecological factors play a critical role in mediating the effects of climate and urbanization on body size. Larger mammals and species that utilize thermal buffering are more sensitive to warmer temperatures, while flexibility in activity time appears to be advantageous in urbanized areas. This work highlights the value of using digitized, natural history data to track how human disturbance drives morphological variation. Anthropogenically-driven climate change is responsible for body size decreases in mammals. Using an important dataset of historically-collected data and data from continental-scale survey efforts from the National Ecological Observatory Network, Hantak et al. show that urbanization plays an important role in mediating this dynamic.
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Affiliation(s)
- Maggie M Hantak
- Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, FL, USA.
| | - Bryan S McLean
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC, USA
| | - Daijiang Li
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA.,Center for Computation & Technology, Louisiana State University, Baton Rouge, LA, USA
| | - Robert P Guralnick
- Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, FL, USA.
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3
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Body mass and physical changes of reintroduced Asiatic black bears. EUR J WILDLIFE RES 2021. [DOI: 10.1007/s10344-021-01514-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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4
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Wilson AE, Wismer D, Stenhouse G, Coops NC, Janz DM. Landscape condition influences energetics, reproduction, and stress biomarkers in grizzly bears. Sci Rep 2021; 11:12124. [PMID: 34108541 PMCID: PMC8190091 DOI: 10.1038/s41598-021-91595-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 05/21/2021] [Indexed: 02/05/2023] Open
Abstract
Environmental change has been shown to influence mammalian distribution, habitat use, and behavior; however, few studies have investigated the impact on physiological function. This study aimed to determine the influence of landscape condition on the expression of target proteins related to energetics, reproduction, and stress in grizzly bears. We hypothesized that changes in landscape condition explains protein expression. Skin biopsies were collected from free-ranging grizzly bears in Alberta, Canada from 2013-2019 (n = 86 individuals). We used an information theoretic approach to develop 11 a priori candidate generalized linear mixed models to explain protein expression. We compared models using Akaike Information Criteria (AICc) weights and averaged models with ΔAICc < 2 for each protein. Food resources, represented by increased distance to coal mines and decreased crown closure, positively influenced energetic proteins (adiponectin and alpha-1-acid glycoprotein). Proteins related to reproduction (ceruloplasmin and serpin B5) were positively associated with increased wetland and upland food resources in addition to movement, but negatively associated with increased distance to roads. One stress related protein, complement C3, was positively influenced by increased percent conifer. Given the need to detect emerging threats to wildlife, we suggest the assessment of physiological function will lead to improved monitoring of species in rapidly changing landscapes.
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Affiliation(s)
- Abbey E. Wilson
- grid.25152.310000 0001 2154 235XDepartment of Veterinary Biomedical Sciences, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N 5B4 Canada ,Toxicology Centre, 44 Campus Drive, Saskatoon, SK S7N 5B3 Canada
| | - Dan Wismer
- fRI Research, Grizzly Bear Program, 1176 Switzer Drive, Hinton, AB T7V 1V3 Canada
| | - Gordon Stenhouse
- fRI Research, Grizzly Bear Program, 1176 Switzer Drive, Hinton, AB T7V 1V3 Canada
| | - Nicholas C. Coops
- grid.17091.3e0000 0001 2288 9830Department of Forest Resource Management, University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4 Canada
| | - David M. Janz
- grid.25152.310000 0001 2154 235XDepartment of Veterinary Biomedical Sciences, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N 5B4 Canada ,Toxicology Centre, 44 Campus Drive, Saskatoon, SK S7N 5B3 Canada
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5
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McClelland CJ, Coops NC, Kearney SP, Burton AC, Nielsen SE, Stenhouse GB. Variations in grizzly bear habitat selection in relation to the daily and seasonal availability of annual plant-food resources. ECOL INFORM 2020. [DOI: 10.1016/j.ecoinf.2020.101116] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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6
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Pollock SZ, Whittington J, Nielsen SE, Clair CC. Spatiotemporal railway use by grizzly bears in Canada's Rocky Mountains. J Wildl Manage 2019. [DOI: 10.1002/jwmg.21750] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sonya Z. Pollock
- University of Alberta, Department of Biological Sciences Edmonton AB T6G 2E9 Canada
| | | | - Scott E. Nielsen
- University of AlbertaDepartment of Renewable Resources Edmonton AB T6G 2H1 Canada
| | - Colleen C. Clair
- University of AlbertaDepartment of Biological Sciences Edmonton AB T6G 2E9 Canada
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7
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Bowen L, Miles AK, Waters S, Gustine D, Joly K, Hilderbrand G. Using Gene Transcription to Assess Ecological and Anthropological Stressors in Brown Bears. ECOHEALTH 2018; 15:121-131. [PMID: 29168050 DOI: 10.1007/s10393-017-1287-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 09/25/2017] [Accepted: 10/30/2017] [Indexed: 06/07/2023]
Abstract
Increasingly, population- and ecosystem-level health assessments are performed using sophisticated molecular tools. Advances in molecular technology enable the identification of synergistic effects of multiple stressors on the individual physiology of different species. Brown bears (Ursus arctos) are an apex predator; thus, they are ideal candidates for detecting potentially ecosystem-level systemic perturbations using molecular-based tools. We used gene transcription to analyze 130 brown bear samples from three National Parks and Preserves in Alaska. Although the populations we studied are apparently stable in abundance and exist within protected and intact environments, differences in transcript profiles were noted. The most prevalent differences were among locations. The transcript patterns among groups reflect the influence of environmental factors, such as nutritional status, disease, and xenobiotic exposure. However, these profiles also likely represent baselines for each unique environment by which future measures can be made to identify early indication of population-level changes due to, for example, increasing Arctic temperatures. Some of those environmental changes are predicted to be potentially positive for brown bears, but other effects such as the manifestation of disease or indirect effects of oceanic acidification may produce negative impacts.
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Affiliation(s)
- Lizabeth Bowen
- U.S. Geological Survey, Western Ecological Research Center, University of California, Davis Field Station, Davis, CA, 95616, USA.
| | - A Keith Miles
- U.S. Geological Survey, Western Ecological Research Center, University of California, Davis Field Station, Davis, CA, 95616, USA
| | - Shannon Waters
- U.S. Geological Survey, Western Ecological Research Center, University of California, Davis Field Station, Davis, CA, 95616, USA
| | - Dave Gustine
- National Park Service, Grand Teton National Park, PO Box 170, Moose, WY, 83012, USA
| | - Kyle Joly
- National Park Service, Gates of the Arctic National Park and Preserve, 4175 Geist Road, Fairbanks, AK, 99709, USA
| | - Grant Hilderbrand
- U.S. Geological Survey, Alaska Science Center, Anchorage, AK, 99508, USA
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8
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Cattet M, Stenhouse GB, Boulanger J, Janz DM, Kapronczai L, Swenson JE, Zedrosser A. Can concentrations of steroid hormones in brown bear hair reveal age class? CONSERVATION PHYSIOLOGY 2018; 6:coy001. [PMID: 29399362 PMCID: PMC5788069 DOI: 10.1093/conphys/coy001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 12/17/2017] [Accepted: 01/05/2018] [Indexed: 06/01/2023]
Abstract
Although combining genetic and endocrine data from non-invasively collected hair samples has potential to improve the conservation of threatened mammals, few studies have evaluated this opportunity. In this study, we determined if steroid hormone (testosterone, progesterone, estradiol and cortisol) concentration profiles in 169 hair samples collected from free-ranging brown bears (Ursus arctos) could be used to accurately discriminate between immature and adult bears within each sex. Because hair samples were acquired opportunistically, we also needed to establish if interactions between hormones and several non-hormone factors (ordinal day, year, contact method, study area) were associated with age class. For each sex, we first compared a suite of candidate models by Akaike Information Criteria model selection, using different adult-age thresholds (3, 4 and 5 years), to determine the most supported adult age. Because hair hormone levels better reflect the endocrine state at an earlier time, possibly during the previous year, then at the time of sampling, we re-analysed the data, excluding the records for bears at the adult-age threshold, to establish if classification accuracy improved. For both sexes, candidate models were most supported based on a 3-year-old adult-age threshold. Classification accuracy did not improve with the 3-year-old bear data excluded. Male age class was predicted with a high degree of accuracy (88.4%) based on the concomitant concentrations of all four hormones. Female age class was predicted with less accuracy (77.1%) based only on testosterone and cortisol. Accuracy was reduced for females, primarily because we had poor success in correctly classifying immature bears (60%) whereas classification success for adult females was similar to that for males (84.5%). Given the small and unbalanced sample used in this study, our findings should be viewed as preliminary, but they should also provide a basis for more comprehensive future studies.
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Affiliation(s)
- Marc Cattet
- RGL Recovery Wildlife Health & Veterinary Services, 415 Mount Allison Crescent, Saskatoon, Saskatchewan S7H 4A6, Canada
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada
| | - Gordon B Stenhouse
- fRI Research and Alberta Environment and Parks, 1176 Switzer Drive, Hinton, Alberta T7V 1X6, Canada
| | - John Boulanger
- Integrated Ecological Research, 924 Innes Street, Nelson, British Columbia V1L 5T2, Canada
| | - David M Janz
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada
| | - Luciene Kapronczai
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, Saskatchewan S7N 5B3, Canada
| | - Jon E Swenson
- Faculty of Environmental Sciences and Nature Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432 Ås, Norway and Norwegian Institute for Nature Research, Høgskoleringen 9, 7034 Trondheim, Norway
| | - Andreas Zedrosser
- Department of Natural Sciences and Environmental Health, Telemark University College of Southeast Norway, NO-3800 Bø i Telemark, Norway
- Department for Integrative Biology, Institute for Wildlife Biology and Game Management, University for Natural Resources and Life Sciences, Vienna A-1180, Austria
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9
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Nielsen SE, Larsen TA, Stenhouse GB, Coogan SCP. Complementary food resources of carnivory and frugivory affect local abundance of an omnivorous carnivore. OIKOS 2016. [DOI: 10.1111/oik.03144] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Scott E. Nielsen
- Dept of Renewable Resources; Univ. of Alberta; 751 General Services Building Edmonton AB T6G 2H1 Canada
| | | | | | - Sean C. P. Coogan
- Dept of Renewable Resources; Univ. of Alberta; 751 General Services Building Edmonton AB T6G 2H1 Canada
- School of Life and Environmental Sciences and the Charles Perkins Centre; Univ. of Sydney; Sydney NSW Australia
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10
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Canale CI, Ozgul A, Allainé D, Cohas A. Differential plasticity of size and mass to environmental change in a hibernating mammal. GLOBAL CHANGE BIOLOGY 2016; 22:3286-3303. [PMID: 26994312 DOI: 10.1111/gcb.13286] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 02/23/2016] [Accepted: 02/29/2016] [Indexed: 06/05/2023]
Abstract
Morphological changes following changes in species' distribution and phenology have been suggested to be the third universal response to global environmental change. Although structural size and body mass result from different genetic, physiological, and ecological mechanisms, they are used interchangeably in studies evaluating population responses to environmental change. Using a 22-year (1991-2013) dataset including 1768 individuals, we investigated the coupled dynamics of size and mass in a hibernating mammal, the Alpine marmot (Marmota marmota), in response to local environmental conditions. We (i) quantified temporal trends in both traits, (ii) determined the environmental drivers of trait dynamics, and (iii) identified the life-history processes underlying the observed changes. Both phenotypic traits were followed through life: we focused on the initial trait value (juvenile size and mass) and later-life development (annual change in size [Δsize] and mass [Δmass]). First, we demonstrated contrasting dynamics between size and mass over the study period. Juvenile size and subsequent Δsize showed significant declines, whereas juvenile mass and subsequent Δmass remained constant. As a consequence of smaller size associated with a similar mass, individuals were in better condition in recent years. Second, size and mass showed different sensitivities to environmental variables. Both traits benefited from early access to resources in spring, whereas Δmass, particularly in early life, also responded to summer and winter conditions. Third, the interannual variation in both traits was caused by changes in early life development. Our study supports the importance of considering the differences between size and mass responses to the environment when evaluating the mechanisms underlying population dynamics. The current practice of focusing on only one trait in population modeling can lead to misleading conclusions when evaluating species' resilience to contemporary climate change.
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Affiliation(s)
- Cindy I Canale
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Arpat Ozgul
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Dominique Allainé
- UMR-CNRS 5558, Laboratoire de Biométrie et Biologie Evolutive, Université Claude Bernard, Lyon 1, 43 Bd. du 11 novembre 1918, F-69622, Villeurbanne Cedex, France
| | - Aurelie Cohas
- UMR-CNRS 5558, Laboratoire de Biométrie et Biologie Evolutive, Université Claude Bernard, Lyon 1, 43 Bd. du 11 novembre 1918, F-69622, Villeurbanne Cedex, France
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11
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López-Alfaro C, Coogan SCP, Robbins CT, Fortin JK, Nielsen SE. Assessing Nutritional Parameters of Brown Bear Diets among Ecosystems Gives Insight into Differences among Populations. PLoS One 2015; 10:e0128088. [PMID: 26083536 PMCID: PMC4470632 DOI: 10.1371/journal.pone.0128088] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 04/22/2015] [Indexed: 11/19/2022] Open
Abstract
Food habit studies are among the first steps used to understand wildlife-habitat relationships. However, these studies are in themselves insufficient to understand differences in population productivity and life histories, because they do not provide a direct measure of the energetic value or nutritional composition of the complete diet. Here, we developed a dynamic model integrating food habits and nutritional information to assess nutritional parameters of brown bear (Ursus arctos) diets among three interior ecosystems of North America. Specifically, we estimate the average amount of digestible energy and protein (per kilogram fresh diet) content in the diet and across the active season by bears living in western Alberta, the Flathead River (FR) drainage of southeast British Columbia, and the Greater Yellowstone Ecosystem (GYE). As well, we estimate the proportion of energy and protein in the diet contributed by different food items, thereby highlighting important food resources in each ecosystem. Bear diets in Alberta had the lowest levels of digestible protein and energy through all seasons, which might help explain the low reproductive rates of this population. The FR diet had protein levels similar to the recent male diet in the GYE during spring, but energy levels were lower during late summer and fall. Historic and recent diets in GYE had the most energy and protein, which is consistent with their larger body sizes and higher population productivity. However, a recent decrease in consumption of trout (Oncorhynchus clarki), whitebark pine nuts (Pinus albicaulis), and ungulates, particularly elk (Cervus elaphus), in GYE bears has decreased the energy and protein content of their diet. The patterns observed suggest that bear body size and population densities are influenced by seasonal availability of protein an energy, likely due in part to nutritional influences on mass gain and reproductive success.
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Affiliation(s)
- Claudia López-Alfaro
- Department of Renewable Resources, University of Alberta, 751 GSB, Edmonton, T6G 2H1, AB, Canada
- Departamento de Ciencias Ambientales y Recursos Naturales Renovables, Universidad de Chile, Av. Santa Rosa, 11315, Casilla 9206, Santiago Chile
- * E-mail:
| | - Sean C. P. Coogan
- Department of Renewable Resources, University of Alberta, 751 GSB, Edmonton, T6G 2H1, AB, Canada
- School of Biological Sciences and the Charles Perkins Centre, University of Sydney, Sydney, NSW 2006, Australia
| | - Charles T. Robbins
- School of the Environment and School of Biological Sciences, Washington State University, Pullman, WA, United States of America
| | - Jennifer K. Fortin
- School of Biological Sciences, Washington State University, Pullman, WA, United States of America
| | - Scott E. Nielsen
- Department of Renewable Resources, University of Alberta, 751 GSB, Edmonton, T6G 2H1, AB, Canada
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12
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Boulanger J, Stenhouse GB. The impact of roads on the demography of grizzly bears in Alberta. PLoS One 2014; 9:e115535. [PMID: 25532035 PMCID: PMC4274100 DOI: 10.1371/journal.pone.0115535] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 11/25/2014] [Indexed: 11/19/2022] Open
Abstract
One of the principal factors that have reduced grizzly bear populations has been the creation of human access into grizzly bear habitat by roads built for resource extraction. Past studies have documented mortality and distributional changes of bears relative to roads but none have attempted to estimate the direct demographic impact of roads in terms of both survival rates, reproductive rates, and the interaction of reproductive state of female bears with survival rate. We applied a combination of survival and reproductive models to estimate demographic parameters for threatened grizzly bear populations in Alberta. Instead of attempting to estimate mean trend we explored factors which caused biological and spatial variation in population trend. We found that sex and age class survival was related to road density with subadult bears being most vulnerable to road-based mortality. A multi-state reproduction model found that females accompanied by cubs of the year and/or yearling cubs had lower survival rates compared to females with two year olds or no cubs. A demographic model found strong spatial gradients in population trend based upon road density. Threshold road densities needed to ensure population stability were estimated to further refine targets for population recovery of grizzly bears in Alberta. Models that considered lowered survival of females with dependant offspring resulted in lower road density thresholds to ensure stable bear populations. Our results demonstrate likely spatial variation in population trend and provide an example how demographic analysis can be used to refine and direct conservation measures for threatened species.
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Affiliation(s)
- John Boulanger
- Integrated Ecological Research, Nelson, British Columbia, Canada
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13
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Bourbonnais ML, Nelson TA, Cattet MRL, Darimont CT, Stenhouse GB, Janz DM. Environmental factors and habitat use influence body condition of individuals in a species at risk, the grizzly bear. CONSERVATION PHYSIOLOGY 2014; 2:cou043. [PMID: 27293664 PMCID: PMC4732474 DOI: 10.1093/conphys/cou043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 08/20/2014] [Accepted: 08/21/2014] [Indexed: 05/30/2023]
Abstract
Metrics used to quantify the condition or physiological states of individuals provide proactive mechanisms for understanding population dynamics in the context of environmental factors. Our study examined how anthropogenic disturbance, habitat characteristics and hair cortisol concentrations interpreted as a sex-specific indicator of potential habitat net-energy demand affect the body condition of grizzly bears (n = 163) in a threatened population in Alberta, Canada. We quantified environmental variables by modelling spatial patterns of individual habitat use based on global positioning system telemetry data. After controlling for gender, age and capture effects, we assessed the influence of biological and environmental variables on body condition using linear mixed-effects models in an information theoretical approach. Our strongest model suggested that body condition was improved when patterns of habitat use included greater vegetation productivity, increased influence of forest harvest blocks and oil and gas well sites, and a higher percentage of regenerating and coniferous forest. However, body condition was negatively affected by habitat use in close proximity to roads and in areas where potential energetic demands were high. Poor body condition was also associated with increased selection of parks and protected areas and greater seasonal vegetation productivity. Adult females, females with cubs-of-year, juvenile females and juvenile males were in poorer body condition compared with adult males, suggesting that intra-specific competition and differences in habitat use based on gender and age may influence body condition dynamics. Habitat net-energy demand also tended to be higher in areas used by females which, combined with observed trends in body condition, could affect reproductive success in this threatened population. Our results highlight the importance of considering spatiotemporal variability in environmental factors and habitat use when assessing the body condition of individuals. Long-term and large-scale monitoring of the physiological state of individuals provides a more comprehensive approach to support management and conservation of species at risk.
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Affiliation(s)
- Mathieu L. Bourbonnais
- Spatial Pattern Analysis and Research Laboratory, Department of Geography, University of Victoria, Victoria, British Columbia, Canada V8W 3R4
| | - Trisalyn A. Nelson
- Spatial Pattern Analysis and Research Laboratory, Department of Geography, University of Victoria, Victoria, British Columbia, Canada V8W 3R4
| | - Marc R. L. Cattet
- Canadian Wildlife Health Cooperative, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
| | - Chris T. Darimont
- Applied Conservation Science Laboratory, Department of Geography, University of Victoria, Victoria, British Columbia, Canada V8W 3R4
| | | | - David M. Janz
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
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14
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Cattet M, Macbeth BJ, Janz DM, Zedrosser A, Swenson JE, Dumond M, Stenhouse GB. Quantifying long-term stress in brown bears with the hair cortisol concentration: a biomarker that may be confounded by rapid changes in response to capture and handling. CONSERVATION PHYSIOLOGY 2014; 2:cou026. [PMID: 27293647 DOI: 10.1093/conphys/cou26] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/26/2014] [Accepted: 05/29/2014] [Indexed: 05/20/2023]
Abstract
The measurement of cortisol in hair is becoming important in studying the role of stress in the life history, health and ecology of wild mammals. The hair cortisol concentration (HCC) is generally believed to be a reliable indicator of long-term stress that can reflect frequent or prolonged activation of the hypothalamic-pituitary-adrenal axis over weeks to months through passive diffusion from the blood supply to the follicular cells that produce the hair. Diffusion of cortisol from tissues surrounding the follicle and glandular secretions (sebum and sweat) that coat the growing hair may also affect the HCC, but the extent of these effects is thought to be minimal. In this study, we report on a range of factors that are associated with, and possibly influence, cortisol concentrations in the hair of free-ranging brown bears (Ursus arctos). Through two levels of analyses that differed in sample sizes and availability of predictor variables, we identified the presence or absence of capture, restraint and handling, as well as different methods of capture, as significant factors that appeared to influence HCC in a time frame that was too short (minutes to hours) to be explained by passive diffusion from the blood supply alone. Furthermore, our results suggest that HCC was altered after hair growth had ceased and blood supply to the hair follicle was terminated. However, we also confirmed that HCC was inversely associated with brown bear body condition and was, therefore, responsive to diminished food availability/quality and possibly other long-term stressors that affect body condition. Collectively, our findings emphasize the importance of further elucidating the mechanisms of cortisol accumulation in hair and the influence of long- and short-term stressors on these mechanisms.
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Affiliation(s)
- Marc Cattet
- Canadian Wildlife Health Cooperative, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
| | - Bryan J Macbeth
- Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4Z6
| | - David M Janz
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
| | - Andreas Zedrosser
- Department of Environmental and Health Studies, Telemark University College, 3800 Bø, Norway
| | - Jon E Swenson
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Mathieu Dumond
- Department of Environment, Government of Nunavut, Kugluktuk, Nunavut, Canada X0B 0E0
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15
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Cattet M, Macbeth BJ, Janz DM, Zedrosser A, Swenson JE, Dumond M, Stenhouse GB. Quantifying long-term stress in brown bears with the hair cortisol concentration: a biomarker that may be confounded by rapid changes in response to capture and handling. CONSERVATION PHYSIOLOGY 2014; 2:cou026. [PMID: 27293647 PMCID: PMC4732478 DOI: 10.1093/conphys/cou026] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/26/2014] [Accepted: 05/29/2014] [Indexed: 05/19/2023]
Abstract
The measurement of cortisol in hair is becoming important in studying the role of stress in the life history, health and ecology of wild mammals. The hair cortisol concentration (HCC) is generally believed to be a reliable indicator of long-term stress that can reflect frequent or prolonged activation of the hypothalamic-pituitary-adrenal axis over weeks to months through passive diffusion from the blood supply to the follicular cells that produce the hair. Diffusion of cortisol from tissues surrounding the follicle and glandular secretions (sebum and sweat) that coat the growing hair may also affect the HCC, but the extent of these effects is thought to be minimal. In this study, we report on a range of factors that are associated with, and possibly influence, cortisol concentrations in the hair of free-ranging brown bears (Ursus arctos). Through two levels of analyses that differed in sample sizes and availability of predictor variables, we identified the presence or absence of capture, restraint and handling, as well as different methods of capture, as significant factors that appeared to influence HCC in a time frame that was too short (minutes to hours) to be explained by passive diffusion from the blood supply alone. Furthermore, our results suggest that HCC was altered after hair growth had ceased and blood supply to the hair follicle was terminated. However, we also confirmed that HCC was inversely associated with brown bear body condition and was, therefore, responsive to diminished food availability/quality and possibly other long-term stressors that affect body condition. Collectively, our findings emphasize the importance of further elucidating the mechanisms of cortisol accumulation in hair and the influence of long- and short-term stressors on these mechanisms.
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Affiliation(s)
- Marc Cattet
- Canadian Wildlife Health Cooperative, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
- Corresponding author: Canadian Wildlife Health Cooperative, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4. Tel: +1 306 966 2162.
| | - Bryan J. Macbeth
- Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4Z6
| | - David M. Janz
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
| | - Andreas Zedrosser
- Department of Environmental and Health Studies, Telemark University College, 3800 Bø, Norway
| | - Jon E. Swenson
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Mathieu Dumond
- Department of Environment, Government of Nunavut, Kugluktuk, Nunavut, Canada X0B 0E0
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16
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Shafer ABA, Nielsen SE, Northrup JM, Stenhouse GB. Linking genotype, ecotype, and phenotype in an intensively managed large carnivore. Evol Appl 2013; 7:301-12. [PMID: 24567749 PMCID: PMC3927890 DOI: 10.1111/eva.12122] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 09/16/2013] [Indexed: 01/14/2023] Open
Abstract
Numerous factors influence fitness of free-ranging animals, yet often these are uncharacterized. We integrated GPS habitat use data and genetic profiling to determine their influence on fitness proxies (mass, length, and body condition) in a threatened population of grizzly bears (Ursus arctos) in Alberta, Canada. We detected distinct genetic and habitat use (ecotype) clusters, with individual cluster assignments, or genotype/ecotype, being correlated (Pearson r = 0.34, P < 0.01). Related individuals showed evidence of similar habitat use patterns, irrespective of geographic distance and sex. Fitness proxies were influenced by sex, age, and habitat use, and homozygosity had a positive effect on these proxies that could be indicative of outbreeding depression. We further documented over 300 translocations occurring in the province since the 1970s, often to areas with significantly different habitat. We argue this could be unintentionally causing the pattern of outbreeding, although the heterozygosity correlation may instead be explained by the energetic costs associated with larger body size. The observed patterns, together with the unprecedented human-mediated migrations, make understanding the link between genotype, ecotype, and phenotype and mechanisms behind the negative heterozygosity-fitness correlations critical for management and conservation of this species.
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Affiliation(s)
- Aaron B A Shafer
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala Universitet Uppsala, Sweden ; Department of Renewable Resources, University of Alberta Edmonton, AB, Canada
| | - Scott E Nielsen
- Department of Renewable Resources, University of Alberta Edmonton, AB, Canada
| | - Joseph M Northrup
- Department of Fish, Wildlife and Conservation Biology, Colorado State University Fort Collins, CO, USA
| | - Gordon B Stenhouse
- Fish and Wildlife Division, Foothills Research Institute and Alberta Environment and Sustainable Resource Development Hinton, AB, Canada
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