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...
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ftunivtasecite:oai:ecite.utas.edu.au:31673 2023-05-15T16:05:37+02:00 At-sea distribution of female southern elephant seals relative to variation in ocean surface properties Bradshaw, CJA Higgins, J Michael, KJ Wotherspoon, SJ Hindell, MA 2004 https://doi.org/10.1016/j.icesjms.2004.07.012 http://ecite.utas.edu.au/31673 en eng Elsevier Ltd http://dx.doi.org/10.1016/j.icesjms.2004.07.012 Bradshaw, CJA and Higgins, J and Michael, KJ and Wotherspoon, SJ and Hindell, MA, At-sea distribution of female southern elephant seals relative to variation in ocean surface properties, ICES Journal of Marine Science, 61, (6) pp. 1014-1027. ISSN 1054-3139 (2004) [Refereed Article] http://ecite.utas.edu.au/31673 Environmental Sciences Environmental Science and Management Wildlife and Habitat Management Refereed Article PeerReviewed 2004 ftunivtasecite https://doi.org/10.1016/j.icesjms.2004.07.012 2019-12-13T21:11:13Z 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 OC 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. 2004 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved. Article in Journal/Newspaper Elephant Seals Sea ice Southern Elephant Seals eCite UTAS (University of Tasmania) Gam ENVELOPE(-57.955,-57.955,-61.923,-61.923) ICES Journal of Marine Science 61 6 1014 1027 |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Environmental Sciences Environmental Science and Management Wildlife and Habitat Management |
spellingShingle |
Environmental Sciences Environmental Science and Management Wildlife and Habitat Management Bradshaw, CJA Higgins, J Michael, KJ Wotherspoon, SJ Hindell, MA At-sea distribution of female southern elephant seals relative to variation in ocean surface properties |
topic_facet |
Environmental Sciences Environmental Science and Management Wildlife and Habitat Management |
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 OC 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. 2004 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Bradshaw, CJA Higgins, J Michael, KJ Wotherspoon, SJ Hindell, MA |
author_facet |
Bradshaw, CJA Higgins, J Michael, KJ Wotherspoon, SJ Hindell, MA |
author_sort |
Bradshaw, CJA |
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 Ltd |
publishDate |
2004 |
url |
https://doi.org/10.1016/j.icesjms.2004.07.012 http://ecite.utas.edu.au/31673 |
long_lat |
ENVELOPE(-57.955,-57.955,-61.923,-61.923) |
geographic |
Gam |
geographic_facet |
Gam |
genre |
Elephant Seals Sea ice Southern Elephant Seals |
genre_facet |
Elephant Seals Sea ice Southern Elephant Seals |
op_relation |
http://dx.doi.org/10.1016/j.icesjms.2004.07.012 Bradshaw, CJA and Higgins, J and Michael, KJ and Wotherspoon, SJ and Hindell, MA, At-sea distribution of female southern elephant seals relative to variation in ocean surface properties, ICES Journal of Marine Science, 61, (6) pp. 1014-1027. ISSN 1054-3139 (2004) [Refereed Article] http://ecite.utas.edu.au/31673 |
op_doi |
https://doi.org/10.1016/j.icesjms.2004.07.012 |
container_title |
ICES Journal of Marine Science |
container_volume |
61 |
container_issue |
6 |
container_start_page |
1014 |
op_container_end_page |
1027 |
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1766401518529937408 |