The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures
There is increasing emphasis put on the correlation of marine predator behaviour and foraging performance with the bio-physical properties of the ocean environment. However, spatial error in the estimated position of animals and the accuracy of interpolated, physical oceanographic data require the a...
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Online Access: | https://doi.org/10.1006/jmsc.2002.1246 http://ecite.utas.edu.au/25340 |
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ftunivtasecite:oai:ecite.utas.edu.au:25340 2023-05-15T16:05:25+02:00 The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures Bradshaw, CJA Hindell, MA Michael, KJ Sumner, MD 2002 https://doi.org/10.1006/jmsc.2002.1246 http://ecite.utas.edu.au/25340 en eng Academic Press Ltd Elsevier Science Ltd http://dx.doi.org/10.1006/jmsc.2002.1246 Bradshaw, CJA and Hindell, MA and Michael, KJ and Sumner, MD, The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures, ICES Journal of Marine Science, 59, (4) pp. 770-781. ISSN 1054-3139 (2002) [Refereed Article] http://ecite.utas.edu.au/25340 Environmental Sciences Environmental Science and Management Wildlife and Habitat Management Refereed Article PeerReviewed 2002 ftunivtasecite https://doi.org/10.1006/jmsc.2002.1246 2019-12-13T21:06:29Z There is increasing emphasis put on the correlation of marine predator behaviour and foraging performance with the bio-physical properties of the ocean environment. However, spatial error in the estimated position of animals and the accuracy of interpolated, physical oceanographic data require the assessment of the appropriate spatial resolution at which to assess relationships. We recorded surface temperature data from 17 archival tags attached to female southern elephant seals at Macquarie Island during the post-lactation foraging trip of 1999-2000. Archival-tag temperature data were associated with twice-daily, at-sea positions derived from light levels (i.e., "geo-location"). We compared these surface temperatures and their associated spatial error to satellite-derived Multi-Channel Sea Surface Temperature (MCSST) data to assess at what spatial scale the agreement between the two data sources was highest. We considered scales from 50 50 km through to 500 500 km grid cells, at 50 50 km increments. Averaged over all individuals and assessed in fortnightly time periods, we found a peak in agreement between the mean surface temperature recorded by the archival tags and the MCSST data at 350 350 km grid cells (122 500 km2). We used logistic regression model selection to examine the effects of spatial scale, time period, latitude, longitude, and MCSST variance per grid cell on the agreement between the data sources. The most parsimonious model included all main effects, and a significant interaction between time period and latitude. There was also a trend for reduced agreement at higher latitudes, and there was a peak in temperature agreement in the general region around 180 longitude. There were two peaks in agreement during the early and latter parts of the post-lactation foraging trip, resulting probably from the more northerly latitudes travelled during these times and the improved MCSST coverage in the summer months. The 350 350 km scale recommended by this study should be appropriate for the study of coarse-scale associations between marine predators located using geo-location and physical oceanographic data during summer. However, the approach remains valid for predators located at sea using other positioning methods. 2002 International Council for the Exploration of the Sea. Published by Elsevier Science Ltd. All rights reserved. Article in Journal/Newspaper Elephant Seal Elephant Seals Macquarie Island Southern Elephant Seals eCite UTAS (University of Tasmania) ICES Journal of Marine Science 59 4 770 781 |
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collection |
eCite UTAS (University of Tasmania) |
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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 Hindell, MA Michael, KJ Sumner, MD The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
topic_facet |
Environmental Sciences Environmental Science and Management Wildlife and Habitat Management |
description |
There is increasing emphasis put on the correlation of marine predator behaviour and foraging performance with the bio-physical properties of the ocean environment. However, spatial error in the estimated position of animals and the accuracy of interpolated, physical oceanographic data require the assessment of the appropriate spatial resolution at which to assess relationships. We recorded surface temperature data from 17 archival tags attached to female southern elephant seals at Macquarie Island during the post-lactation foraging trip of 1999-2000. Archival-tag temperature data were associated with twice-daily, at-sea positions derived from light levels (i.e., "geo-location"). We compared these surface temperatures and their associated spatial error to satellite-derived Multi-Channel Sea Surface Temperature (MCSST) data to assess at what spatial scale the agreement between the two data sources was highest. We considered scales from 50 50 km through to 500 500 km grid cells, at 50 50 km increments. Averaged over all individuals and assessed in fortnightly time periods, we found a peak in agreement between the mean surface temperature recorded by the archival tags and the MCSST data at 350 350 km grid cells (122 500 km2). We used logistic regression model selection to examine the effects of spatial scale, time period, latitude, longitude, and MCSST variance per grid cell on the agreement between the data sources. The most parsimonious model included all main effects, and a significant interaction between time period and latitude. There was also a trend for reduced agreement at higher latitudes, and there was a peak in temperature agreement in the general region around 180 longitude. There were two peaks in agreement during the early and latter parts of the post-lactation foraging trip, resulting probably from the more northerly latitudes travelled during these times and the improved MCSST coverage in the summer months. The 350 350 km scale recommended by this study should be appropriate for the study of coarse-scale associations between marine predators located using geo-location and physical oceanographic data during summer. However, the approach remains valid for predators located at sea using other positioning methods. 2002 International Council for the Exploration of the Sea. Published by Elsevier Science Ltd. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Bradshaw, CJA Hindell, MA Michael, KJ Sumner, MD |
author_facet |
Bradshaw, CJA Hindell, MA Michael, KJ Sumner, MD |
author_sort |
Bradshaw, CJA |
title |
The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
title_short |
The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
title_full |
The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
title_fullStr |
The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
title_full_unstemmed |
The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
title_sort |
optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures |
publisher |
Academic Press Ltd Elsevier Science Ltd |
publishDate |
2002 |
url |
https://doi.org/10.1006/jmsc.2002.1246 http://ecite.utas.edu.au/25340 |
genre |
Elephant Seal Elephant Seals Macquarie Island Southern Elephant Seals |
genre_facet |
Elephant Seal Elephant Seals Macquarie Island Southern Elephant Seals |
op_relation |
http://dx.doi.org/10.1006/jmsc.2002.1246 Bradshaw, CJA and Hindell, MA and Michael, KJ and Sumner, MD, The optimal spatial scale for the analysis of elephant seal foraging as determined by geo-location in relation to sea surface temperatures, ICES Journal of Marine Science, 59, (4) pp. 770-781. ISSN 1054-3139 (2002) [Refereed Article] http://ecite.utas.edu.au/25340 |
op_doi |
https://doi.org/10.1006/jmsc.2002.1246 |
container_title |
ICES Journal of Marine Science |
container_volume |
59 |
container_issue |
4 |
container_start_page |
770 |
op_container_end_page |
781 |
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1766401314753871872 |