Brown bear population vital rates
Identifying mechanisms of population change is fundamental for conserving small and declining populations and determining effective management strategies. Few studies, however, have measured the demographic components of population change for small populations of mammals (< 50 individuals). We es...
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ftzenodo:oai:zenodo.org:5949543 2024-09-15T18:40:16+00:00 Brown bear population vital rates McLellan, Michelle 2022-02-02 https://doi.org/10.5061/dryad.h44j0zpjb unknown Zenodo https://zenodo.org/communities/dryad https://doi.org/10.5061/dryad.h44j0zpjb oai:zenodo.org:5949543 info:eu-repo/semantics/openAccess Creative Commons Zero v1.0 Universal https://creativecommons.org/publicdomain/zero/1.0/legalcode juvenile survival reproductive transitions age first reproduction info:eu-repo/semantics/other 2022 ftzenodo https://doi.org/10.5061/dryad.h44j0zpjb 2024-07-27T02:50:49Z Identifying mechanisms of population change is fundamental for conserving small and declining populations and determining effective management strategies. Few studies, however, have measured the demographic components of population change for small populations of mammals (< 50 individuals). We estimated vital rates and trends in two adjacent but genetically distinct, threatened brown bear ( Ursus arctos ) populations in British Columbia, Canada, following the cessation of hunting. One population had approximately 45 resident bears but had some genetic and geographic connectivity to neighbouring populations, while the other population had < 25 individuals and was isolated. We estimated population-specific vital rates by monitoring survival and reproduction of telemetered female bears and their dependent offspring from 2005 to 2018. In the larger, connected population, independent female survival was 1.00 (95% CI: 0.96-1.00) and the survival of cubs in their first year was 0.85 (95% CI: 0.62-0.95). In the smaller, isolated population, independent female survival was 0.81 (95% CI: 0.64-0.93) and first-year cub survival was 0.33 (95% CI: 0.11-0.67). Reproductive rates did not differ between populations. The large differences in age-specific survival estimates resulted in a projected population increase in the larger population (λ = 1.09; 95% CI: 1.04-1.13) and population decrease in the smaller population (λ = 0.84; 95% CI: 0.72-0.95). Low female survival in the smaller population was the result of both continued human-caused mortality and an unusually high rate of natural mortality. Low cub survival may have been due to inbreeding and the loss of genetic diversity common in small populations, or to limited resources. In a systematic literature review, we compared our population trend estimates with those reported for other small populations (< 300 individuals) of brown bears. Results suggest that once brown bear populations become small and isolated, populations rarely increase and, even with intensive ... Other/Unknown Material Ursus arctos Zenodo |
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juvenile survival reproductive transitions age first reproduction |
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juvenile survival reproductive transitions age first reproduction McLellan, Michelle Brown bear population vital rates |
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juvenile survival reproductive transitions age first reproduction |
description |
Identifying mechanisms of population change is fundamental for conserving small and declining populations and determining effective management strategies. Few studies, however, have measured the demographic components of population change for small populations of mammals (< 50 individuals). We estimated vital rates and trends in two adjacent but genetically distinct, threatened brown bear ( Ursus arctos ) populations in British Columbia, Canada, following the cessation of hunting. One population had approximately 45 resident bears but had some genetic and geographic connectivity to neighbouring populations, while the other population had < 25 individuals and was isolated. We estimated population-specific vital rates by monitoring survival and reproduction of telemetered female bears and their dependent offspring from 2005 to 2018. In the larger, connected population, independent female survival was 1.00 (95% CI: 0.96-1.00) and the survival of cubs in their first year was 0.85 (95% CI: 0.62-0.95). In the smaller, isolated population, independent female survival was 0.81 (95% CI: 0.64-0.93) and first-year cub survival was 0.33 (95% CI: 0.11-0.67). Reproductive rates did not differ between populations. The large differences in age-specific survival estimates resulted in a projected population increase in the larger population (λ = 1.09; 95% CI: 1.04-1.13) and population decrease in the smaller population (λ = 0.84; 95% CI: 0.72-0.95). Low female survival in the smaller population was the result of both continued human-caused mortality and an unusually high rate of natural mortality. Low cub survival may have been due to inbreeding and the loss of genetic diversity common in small populations, or to limited resources. In a systematic literature review, we compared our population trend estimates with those reported for other small populations (< 300 individuals) of brown bears. Results suggest that once brown bear populations become small and isolated, populations rarely increase and, even with intensive ... |
format |
Other/Unknown Material |
author |
McLellan, Michelle |
author_facet |
McLellan, Michelle |
author_sort |
McLellan, Michelle |
title |
Brown bear population vital rates |
title_short |
Brown bear population vital rates |
title_full |
Brown bear population vital rates |
title_fullStr |
Brown bear population vital rates |
title_full_unstemmed |
Brown bear population vital rates |
title_sort |
brown bear population vital rates |
publisher |
Zenodo |
publishDate |
2022 |
url |
https://doi.org/10.5061/dryad.h44j0zpjb |
genre |
Ursus arctos |
genre_facet |
Ursus arctos |
op_relation |
https://zenodo.org/communities/dryad https://doi.org/10.5061/dryad.h44j0zpjb oai:zenodo.org:5949543 |
op_rights |
info:eu-repo/semantics/openAccess Creative Commons Zero v1.0 Universal https://creativecommons.org/publicdomain/zero/1.0/legalcode |
op_doi |
https://doi.org/10.5061/dryad.h44j0zpjb |
_version_ |
1810484567632510976 |