Natal dispersal of juvenile arctic ground squirrels in the boreal forest
Natal dispersal is assumed to be costly because of the risk of mortality, yet rarely are movement patterns and survival of dispersers observed directly. We determined the fates and dispersal distances of 150 radio-collared juvenile arctic ground squirrels from 1993 to 1995 at Kluane, Yukon Territory...
Published in: | Canadian Journal of Zoology |
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1999
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Online Access: | http://dx.doi.org/10.1139/z99-072 http://www.nrcresearchpress.com/doi/pdf/10.1139/z99-072 |
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crcansciencepubl:10.1139/z99-072 2024-04-28T08:08:06+00:00 Natal dispersal of juvenile arctic ground squirrels in the boreal forest Byrom, Andrea E Krebs, Charles J 1999 http://dx.doi.org/10.1139/z99-072 http://www.nrcresearchpress.com/doi/pdf/10.1139/z99-072 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Zoology volume 77, issue 7, page 1048-1059 ISSN 0008-4301 1480-3283 Animal Science and Zoology Ecology, Evolution, Behavior and Systematics journal-article 1999 crcansciencepubl https://doi.org/10.1139/z99-072 2024-04-09T06:56:30Z Natal dispersal is assumed to be costly because of the risk of mortality, yet rarely are movement patterns and survival of dispersers observed directly. We determined the fates and dispersal distances of 150 radio-collared juvenile arctic ground squirrels from 1993 to 1995 at Kluane, Yukon Territory, Canada (61°N, 138°W). We tested the hypothesis that dispersal has a high mortality cost, and we also attempted to distinguish among three hypotheses to explain natal dispersal: competition for mates, competition for resources, and inbreeding avoidance. Juveniles were radio-collared at emergence from the natal burrow on five 9-ha grids nested within larger (1 km 2 ) experimental manipulations: two controls, a predator exclosure, a food-supplemented grid, and a predator exclosure + food grid. In all years and on all areas, dispersing juveniles were more likely to die than philopatric squirrels, and the risk of mortality increased with distance from the natal burrow for both sexes. Overall, survival of philopatric squirrels was 73%, whereas survival of dispersing squirrels ranged from a maximum of 40% to a minimum of 25%. Juvenile females were strongly philopatric independent of population density, except on the predator exclosure + food grid in 1995, where population density was extremely high and resources other than food were probably limiting. Resource competition may explain patterns of philopatry and dispersal in female arctic ground squirrels. Juvenile males moved farther from their natal site than females and more of them died. Males also had a strong tendency to disperse that was independent of food availability or population density, which suggests that male arctic ground squirrels ultimately may disperse to avoid either inbreeding with female relatives or intrasexual competition for mates. Article in Journal/Newspaper Arctic Yukon Canadian Science Publishing Canadian Journal of Zoology 77 7 1048 1059 |
institution |
Open Polar |
collection |
Canadian Science Publishing |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
Animal Science and Zoology Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Animal Science and Zoology Ecology, Evolution, Behavior and Systematics Byrom, Andrea E Krebs, Charles J Natal dispersal of juvenile arctic ground squirrels in the boreal forest |
topic_facet |
Animal Science and Zoology Ecology, Evolution, Behavior and Systematics |
description |
Natal dispersal is assumed to be costly because of the risk of mortality, yet rarely are movement patterns and survival of dispersers observed directly. We determined the fates and dispersal distances of 150 radio-collared juvenile arctic ground squirrels from 1993 to 1995 at Kluane, Yukon Territory, Canada (61°N, 138°W). We tested the hypothesis that dispersal has a high mortality cost, and we also attempted to distinguish among three hypotheses to explain natal dispersal: competition for mates, competition for resources, and inbreeding avoidance. Juveniles were radio-collared at emergence from the natal burrow on five 9-ha grids nested within larger (1 km 2 ) experimental manipulations: two controls, a predator exclosure, a food-supplemented grid, and a predator exclosure + food grid. In all years and on all areas, dispersing juveniles were more likely to die than philopatric squirrels, and the risk of mortality increased with distance from the natal burrow for both sexes. Overall, survival of philopatric squirrels was 73%, whereas survival of dispersing squirrels ranged from a maximum of 40% to a minimum of 25%. Juvenile females were strongly philopatric independent of population density, except on the predator exclosure + food grid in 1995, where population density was extremely high and resources other than food were probably limiting. Resource competition may explain patterns of philopatry and dispersal in female arctic ground squirrels. Juvenile males moved farther from their natal site than females and more of them died. Males also had a strong tendency to disperse that was independent of food availability or population density, which suggests that male arctic ground squirrels ultimately may disperse to avoid either inbreeding with female relatives or intrasexual competition for mates. |
format |
Article in Journal/Newspaper |
author |
Byrom, Andrea E Krebs, Charles J |
author_facet |
Byrom, Andrea E Krebs, Charles J |
author_sort |
Byrom, Andrea E |
title |
Natal dispersal of juvenile arctic ground squirrels in the boreal forest |
title_short |
Natal dispersal of juvenile arctic ground squirrels in the boreal forest |
title_full |
Natal dispersal of juvenile arctic ground squirrels in the boreal forest |
title_fullStr |
Natal dispersal of juvenile arctic ground squirrels in the boreal forest |
title_full_unstemmed |
Natal dispersal of juvenile arctic ground squirrels in the boreal forest |
title_sort |
natal dispersal of juvenile arctic ground squirrels in the boreal forest |
publisher |
Canadian Science Publishing |
publishDate |
1999 |
url |
http://dx.doi.org/10.1139/z99-072 http://www.nrcresearchpress.com/doi/pdf/10.1139/z99-072 |
genre |
Arctic Yukon |
genre_facet |
Arctic Yukon |
op_source |
Canadian Journal of Zoology volume 77, issue 7, page 1048-1059 ISSN 0008-4301 1480-3283 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/z99-072 |
container_title |
Canadian Journal of Zoology |
container_volume |
77 |
container_issue |
7 |
container_start_page |
1048 |
op_container_end_page |
1059 |
_version_ |
1797577001140224000 |