Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia
Female southern elephant seals, Mirounga leonina, assemble in large groups and each gives birth to a single pup which is nursed for some 3 weeks. Weaning mass is highly variable; some pups are three times as heavy as others at weaning. After weaning, the pup fasts for several weeks before departing...
Published in: | Canadian Journal of Zoology |
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Canadian Science Publishing
1993
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Online Access: | http://dx.doi.org/10.1139/z93-252 http://www.nrcresearchpress.com/doi/pdf/10.1139/z93-252 |
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crcansciencepubl:10.1139/z93-252 2024-09-15T18:04:43+00:00 Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia Arnbom, T. Fedak, M. A. Boyd, I. L. McConnell, B. J. 1993 http://dx.doi.org/10.1139/z93-252 http://www.nrcresearchpress.com/doi/pdf/10.1139/z93-252 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Zoology volume 71, issue 9, page 1772-1781 ISSN 0008-4301 1480-3283 journal-article 1993 crcansciencepubl https://doi.org/10.1139/z93-252 2024-06-27T04:11:01Z Female southern elephant seals, Mirounga leonina, assemble in large groups and each gives birth to a single pup which is nursed for some 3 weeks. Weaning mass is highly variable; some pups are three times as heavy as others at weaning. After weaning, the pup fasts for several weeks before departing to sea. The function of this fast is unknown. We examined the relationships between maternal mass, pup weaning mass, and pup behaviour during the postweaning fast in 377 pups and 128 adult females over four breeding seasons at South Georgia. Pup weaning mass was positively related to maternal postpartum mass, which accounted for 55% of the variation in weaning mass. Over all 4 years male pups were significantly heavier at weaning than female pups (130 vs. 123 kg) but this difference disappeared after maternal mass was controlled for. After fasting for 21–66 days, weaned pups went to sea at an average of 68% of weaning mass. Heavier pups remained on the beach longer after weaning than lighter pups. There was no evidence that pups synchronized their departure to sea. Only male pups were observed to take part in mock fights. With increasing age, weaned pups spent more time in the water. Mortality during the postweaning fast was negligible (0.1 %). The timing of departure of weaned pups may involve a trade-off between an early departure with greater fat (energy) stores but poorer foraging ability and a late departure with increased swimming, diving, and social skills but reduced fat stores. Article in Journal/Newspaper Elephant Seals Mirounga leonina Southern Elephant Seals Canadian Science Publishing Canadian Journal of Zoology 71 9 1772 1781 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
Female southern elephant seals, Mirounga leonina, assemble in large groups and each gives birth to a single pup which is nursed for some 3 weeks. Weaning mass is highly variable; some pups are three times as heavy as others at weaning. After weaning, the pup fasts for several weeks before departing to sea. The function of this fast is unknown. We examined the relationships between maternal mass, pup weaning mass, and pup behaviour during the postweaning fast in 377 pups and 128 adult females over four breeding seasons at South Georgia. Pup weaning mass was positively related to maternal postpartum mass, which accounted for 55% of the variation in weaning mass. Over all 4 years male pups were significantly heavier at weaning than female pups (130 vs. 123 kg) but this difference disappeared after maternal mass was controlled for. After fasting for 21–66 days, weaned pups went to sea at an average of 68% of weaning mass. Heavier pups remained on the beach longer after weaning than lighter pups. There was no evidence that pups synchronized their departure to sea. Only male pups were observed to take part in mock fights. With increasing age, weaned pups spent more time in the water. Mortality during the postweaning fast was negligible (0.1 %). The timing of departure of weaned pups may involve a trade-off between an early departure with greater fat (energy) stores but poorer foraging ability and a late departure with increased swimming, diving, and social skills but reduced fat stores. |
format |
Article in Journal/Newspaper |
author |
Arnbom, T. Fedak, M. A. Boyd, I. L. McConnell, B. J. |
spellingShingle |
Arnbom, T. Fedak, M. A. Boyd, I. L. McConnell, B. J. Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia |
author_facet |
Arnbom, T. Fedak, M. A. Boyd, I. L. McConnell, B. J. |
author_sort |
Arnbom, T. |
title |
Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia |
title_short |
Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia |
title_full |
Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia |
title_fullStr |
Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia |
title_full_unstemmed |
Variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( Mirounga leonina) at South Georgia |
title_sort |
variation in weaning mass of pups in relation to maternal mass, postweaning fast duration, and weaned pup behaviour in southern elephant seals ( mirounga leonina) at south georgia |
publisher |
Canadian Science Publishing |
publishDate |
1993 |
url |
http://dx.doi.org/10.1139/z93-252 http://www.nrcresearchpress.com/doi/pdf/10.1139/z93-252 |
genre |
Elephant Seals Mirounga leonina Southern Elephant Seals |
genre_facet |
Elephant Seals Mirounga leonina Southern Elephant Seals |
op_source |
Canadian Journal of Zoology volume 71, issue 9, page 1772-1781 ISSN 0008-4301 1480-3283 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/z93-252 |
container_title |
Canadian Journal of Zoology |
container_volume |
71 |
container_issue |
9 |
container_start_page |
1772 |
op_container_end_page |
1781 |
_version_ |
1810442330855964672 |