At-sea distribution of female southern elephant seals relative to variation in ocean surface properties
We examined the relationships between physical oceanography (sea surface temperature SST, sea surface height anomaly - SSH, ocean colour - OC, bathymetry - BA, sea-ice concentration - SI, and their associated gradients) and the foraging distribution (time at sea) of female southern elephant seals us...
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ftcharlesdarwin:oai:espace.cdu.edu.au:cdu:1564 2023-07-02T03:29:54+02:00 At-sea distribution of female southern elephant seals relative to variation in ocean surface properties Bradshaw, Corey J. A. Higgins, J. Michael, K. J. Wotherspoon, S. J. Hindell, Mark A. 2004-01-01 http://espace.cdu.edu.au/view/cdu:1564 unknown Elsevier bathymetry elephant seals environmental variation generalized additive model generalized linear model oceanography sea surface temperature antarctic fur seals sperm whale distribution mirounga-leonina oceanographic features foraging ecology king penguins arctocephalus-gazella spatial-distribution macquarie island polar front Journal Article 2004 ftcharlesdarwin 2023-06-12T22:23:32Z We examined the relationships between physical oceanography (sea surface temperature SST, sea surface height anomaly - SSH, ocean colour - OC, bathymetry - BA, sea-ice concentration - SI, and their associated gradients) and the foraging distribution (time at sea) of female southern elephant seals using generalized linear and generalized additive models (GLM and GAM). Using data from 28 separate foraging trips (22 unique individuals) over two years, we found that during the post-lactation trips (summer), the best GLM demonstrated a negative relationship between time at sea and SST and BA, but a positive relationship with SST gradient and SSH. During the post-moult (winter) trips, there was a negative relationship with OC gradient, SSH, and BA. The best post-lactation GAM identified a positive relationship with OC gradient, negative relationships with CC and SST gradient, and a non-linear relationship with SST. For the post-moult trip there was a negative relationship with OC, SST, BA and BA gradient, and a positive relationship with SST gradient. The relationship between the predicted time and observed time at sea was significant only for the post-lactation GAM, although predictability was low. That SST and its gradient predicted a small, but significant proportion of the variation in time at sea is indicative of the frontal zones within this area that are generally more biologically productive than surrounding regions. It appears that coarse-scale oceanographic configuration influences foraging behaviour in southern elephant seals only subtly. Nonetheless, some of the mechanisms influencing predator foraging are congruent with expectations of distribution of marine food resources at coarse spatial scales. (C) 2004 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved. Article in Journal/Newspaper Antarc* Antarctic Antarctic Fur Seals Arctocephalus gazella Elephant Seals King Penguins Macquarie Island Mirounga leonina Sea ice Southern Elephant Seals Sperm whale Charles Darwin University: CDU eSpace Antarctic Gam ENVELOPE(-57.955,-57.955,-61.923,-61.923) |
institution |
Open Polar |
collection |
Charles Darwin University: CDU eSpace |
op_collection_id |
ftcharlesdarwin |
language |
unknown |
topic |
bathymetry elephant seals environmental variation generalized additive model generalized linear model oceanography sea surface temperature antarctic fur seals sperm whale distribution mirounga-leonina oceanographic features foraging ecology king penguins arctocephalus-gazella spatial-distribution macquarie island polar front |
spellingShingle |
bathymetry elephant seals environmental variation generalized additive model generalized linear model oceanography sea surface temperature antarctic fur seals sperm whale distribution mirounga-leonina oceanographic features foraging ecology king penguins arctocephalus-gazella spatial-distribution macquarie island polar front Bradshaw, Corey J. A. Higgins, J. Michael, K. J. Wotherspoon, S. J. Hindell, Mark A. At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
topic_facet |
bathymetry elephant seals environmental variation generalized additive model generalized linear model oceanography sea surface temperature antarctic fur seals sperm whale distribution mirounga-leonina oceanographic features foraging ecology king penguins arctocephalus-gazella spatial-distribution macquarie island polar front |
description |
We examined the relationships between physical oceanography (sea surface temperature SST, sea surface height anomaly - SSH, ocean colour - OC, bathymetry - BA, sea-ice concentration - SI, and their associated gradients) and the foraging distribution (time at sea) of female southern elephant seals using generalized linear and generalized additive models (GLM and GAM). Using data from 28 separate foraging trips (22 unique individuals) over two years, we found that during the post-lactation trips (summer), the best GLM demonstrated a negative relationship between time at sea and SST and BA, but a positive relationship with SST gradient and SSH. During the post-moult (winter) trips, there was a negative relationship with OC gradient, SSH, and BA. The best post-lactation GAM identified a positive relationship with OC gradient, negative relationships with CC and SST gradient, and a non-linear relationship with SST. For the post-moult trip there was a negative relationship with OC, SST, BA and BA gradient, and a positive relationship with SST gradient. The relationship between the predicted time and observed time at sea was significant only for the post-lactation GAM, although predictability was low. That SST and its gradient predicted a small, but significant proportion of the variation in time at sea is indicative of the frontal zones within this area that are generally more biologically productive than surrounding regions. It appears that coarse-scale oceanographic configuration influences foraging behaviour in southern elephant seals only subtly. Nonetheless, some of the mechanisms influencing predator foraging are congruent with expectations of distribution of marine food resources at coarse spatial scales. (C) 2004 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Bradshaw, Corey J. A. Higgins, J. Michael, K. J. Wotherspoon, S. J. Hindell, Mark A. |
author_facet |
Bradshaw, Corey J. A. Higgins, J. Michael, K. J. Wotherspoon, S. J. Hindell, Mark A. |
author_sort |
Bradshaw, Corey J. A. |
title |
At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
title_short |
At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
title_full |
At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
title_fullStr |
At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
title_full_unstemmed |
At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
title_sort |
at-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
publisher |
Elsevier |
publishDate |
2004 |
url |
http://espace.cdu.edu.au/view/cdu:1564 |
long_lat |
ENVELOPE(-57.955,-57.955,-61.923,-61.923) |
geographic |
Antarctic Gam |
geographic_facet |
Antarctic Gam |
genre |
Antarc* Antarctic Antarctic Fur Seals Arctocephalus gazella Elephant Seals King Penguins Macquarie Island Mirounga leonina Sea ice Southern Elephant Seals Sperm whale |
genre_facet |
Antarc* Antarctic Antarctic Fur Seals Arctocephalus gazella Elephant Seals King Penguins Macquarie Island Mirounga leonina Sea ice Southern Elephant Seals Sperm whale |
_version_ |
1770273280714866688 |