Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina)
The evolution of resource specializations is poorly understood, especially in marine systems. The southern elephant seal ( Mirounga leonina ) is the largest of the phocid seals, sexually dimorphic, and thought to prey predominantly on fish and squid. We collected vibrissae from male and female south...
Published in: | Proceedings of the Royal Society B: Biological Sciences |
---|---|
Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
The Royal Society
2006
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1098/rspb.2006.3642 https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2006.3642 https://royalsocietypublishing.org/doi/full-xml/10.1098/rspb.2006.3642 |
id |
crroyalsociety:10.1098/rspb.2006.3642 |
---|---|
record_format |
openpolar |
spelling |
crroyalsociety:10.1098/rspb.2006.3642 2024-09-09T19:38:54+00:00 Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) Lewis, Rebecca O'Connell, Tamsin C Lewis, Mirtha Campagna, Claudio Hoelzel, A. Rus 2006 http://dx.doi.org/10.1098/rspb.2006.3642 https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2006.3642 https://royalsocietypublishing.org/doi/full-xml/10.1098/rspb.2006.3642 en eng The Royal Society https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ Proceedings of the Royal Society B: Biological Sciences volume 273, issue 1603, page 2901-2907 ISSN 0962-8452 1471-2954 journal-article 2006 crroyalsociety https://doi.org/10.1098/rspb.2006.3642 2024-08-26T04:21:02Z The evolution of resource specializations is poorly understood, especially in marine systems. The southern elephant seal ( Mirounga leonina ) is the largest of the phocid seals, sexually dimorphic, and thought to prey predominantly on fish and squid. We collected vibrissae from male and female southern elephant seals, and assessed stable C and N isotope ratios along the length of the vibrissae. Given that whiskers grow slowly, this sampling strategy reflects any variation in feeding behaviour over a period of time. We found that isotopic variation among females was relatively small, and that the apparent prey choice and trophic level of females was different from that for males. Further, males showed a very broad range of trophic/prey choice positions, grouped into several clusters, and this included isotopic values too low to match a broad range of potential fish and cephalopod prey tested. One of these clusters overlapped with data for South American sea lions ( Otaria flavescens ), which were measured for comparison. Both male southern elephant seals and southern sea lions forage over the continental shelf, providing the potential for competition. We discuss the possibility that individual southern elephant seals are pursuing specialist foraging strategies to avoid competition, both with one another, and with the South American sea lions that breed nearby. Article in Journal/Newspaper Elephant Seal Elephant Seals Mirounga leonina Southern Elephant Seal Southern Elephant Seals The Royal Society Proceedings of the Royal Society B: Biological Sciences 273 1603 2901 2907 |
institution |
Open Polar |
collection |
The Royal Society |
op_collection_id |
crroyalsociety |
language |
English |
description |
The evolution of resource specializations is poorly understood, especially in marine systems. The southern elephant seal ( Mirounga leonina ) is the largest of the phocid seals, sexually dimorphic, and thought to prey predominantly on fish and squid. We collected vibrissae from male and female southern elephant seals, and assessed stable C and N isotope ratios along the length of the vibrissae. Given that whiskers grow slowly, this sampling strategy reflects any variation in feeding behaviour over a period of time. We found that isotopic variation among females was relatively small, and that the apparent prey choice and trophic level of females was different from that for males. Further, males showed a very broad range of trophic/prey choice positions, grouped into several clusters, and this included isotopic values too low to match a broad range of potential fish and cephalopod prey tested. One of these clusters overlapped with data for South American sea lions ( Otaria flavescens ), which were measured for comparison. Both male southern elephant seals and southern sea lions forage over the continental shelf, providing the potential for competition. We discuss the possibility that individual southern elephant seals are pursuing specialist foraging strategies to avoid competition, both with one another, and with the South American sea lions that breed nearby. |
format |
Article in Journal/Newspaper |
author |
Lewis, Rebecca O'Connell, Tamsin C Lewis, Mirtha Campagna, Claudio Hoelzel, A. Rus |
spellingShingle |
Lewis, Rebecca O'Connell, Tamsin C Lewis, Mirtha Campagna, Claudio Hoelzel, A. Rus Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) |
author_facet |
Lewis, Rebecca O'Connell, Tamsin C Lewis, Mirtha Campagna, Claudio Hoelzel, A. Rus |
author_sort |
Lewis, Rebecca |
title |
Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) |
title_short |
Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) |
title_full |
Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) |
title_fullStr |
Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) |
title_full_unstemmed |
Sex-specific foraging strategies and resource partitioning in the southern elephant seal ( Mirounga leonina) |
title_sort |
sex-specific foraging strategies and resource partitioning in the southern elephant seal ( mirounga leonina) |
publisher |
The Royal Society |
publishDate |
2006 |
url |
http://dx.doi.org/10.1098/rspb.2006.3642 https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2006.3642 https://royalsocietypublishing.org/doi/full-xml/10.1098/rspb.2006.3642 |
genre |
Elephant Seal Elephant Seals Mirounga leonina Southern Elephant Seal Southern Elephant Seals |
genre_facet |
Elephant Seal Elephant Seals Mirounga leonina Southern Elephant Seal Southern Elephant Seals |
op_source |
Proceedings of the Royal Society B: Biological Sciences volume 273, issue 1603, page 2901-2907 ISSN 0962-8452 1471-2954 |
op_rights |
https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ |
op_doi |
https://doi.org/10.1098/rspb.2006.3642 |
container_title |
Proceedings of the Royal Society B: Biological Sciences |
container_volume |
273 |
container_issue |
1603 |
container_start_page |
2901 |
op_container_end_page |
2907 |
_version_ |
1809908051000426496 |