Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis
Ross seals Ommatophoca rossii are one of the least studied marine mammals, with little known about their foraging ecology. Research to date using bulk stable isotope analysis suggests that Ross seals have a trophic position intermediate between that of Weddell Leptonychotes weddellii and crabeater L...
Published in: | Marine Ecology Progress Series |
---|---|
Main Authors: | , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2019
|
Subjects: | |
Online Access: | https://pure.au.dk/portal/da/publications/trophic-position-and-foraging-ecology-of-ross-weddell-and-crabeater-seals-revealed-by-compoundspecific-isotope-analysis(7eb6ccb3-e910-49ae-b0cf-c5b9188bb958).html https://doi.org/10.3354/meps12856 https://pure.au.dk/ws/files/194491078/m611p001.pdf http://www.scopus.com/inward/record.url?scp=85061499874&partnerID=8YFLogxK |
id |
ftuniaarhuspubl:oai:pure.atira.dk:publications/7eb6ccb3-e910-49ae-b0cf-c5b9188bb958 |
---|---|
record_format |
openpolar |
spelling |
ftuniaarhuspubl:oai:pure.atira.dk:publications/7eb6ccb3-e910-49ae-b0cf-c5b9188bb958 2023-05-15T13:53:31+02:00 Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis Brault, Emily K. Koch, Paul L. Costa, Daniel P. McCarthy, Matthew D. Hückstädt, Luis A. Goetz, Kimberly T. McMahon, Kelton W. Goebel, Michael E. Karlsson, Olle Teilmann, Jonas Harkonen, Tero Harding, Karin C. 2019-02-14 application/pdf https://pure.au.dk/portal/da/publications/trophic-position-and-foraging-ecology-of-ross-weddell-and-crabeater-seals-revealed-by-compoundspecific-isotope-analysis(7eb6ccb3-e910-49ae-b0cf-c5b9188bb958).html https://doi.org/10.3354/meps12856 https://pure.au.dk/ws/files/194491078/m611p001.pdf http://www.scopus.com/inward/record.url?scp=85061499874&partnerID=8YFLogxK eng eng info:eu-repo/semantics/openAccess Brault , E K , Koch , P L , Costa , D P , McCarthy , M D , Hückstädt , L A , Goetz , K T , McMahon , K W , Goebel , M E , Karlsson , O , Teilmann , J , Harkonen , T & Harding , K C 2019 , ' Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis ' , Marine Ecology Progress Series , vol. 611 , pp. 1-18 . https://doi.org/10.3354/meps12856 Amino acids Antarctica Compound-specific isotopes Crabeater Foraging ecology Ross seal Seal Trophic dynamics Weddell seal WEDDELL SEALS crabeater seal article 2019 ftuniaarhuspubl https://doi.org/10.3354/meps12856 2023-01-25T23:54:37Z Ross seals Ommatophoca rossii are one of the least studied marine mammals, with little known about their foraging ecology. Research to date using bulk stable isotope analysis suggests that Ross seals have a trophic position intermediate between that of Weddell Leptonychotes weddellii and crabeater Lobodon carcinophaga seals. However, consumer bulk stable isotope values not only reflect trophic dynamics, but also variations in baseline isotope values, which can be substantial. We used compound-specific isotope analysis of amino acids (CSI-AA) to separate isotopic effects of a shifting baseline versus trophic structure on the foraging ecology of these ecologically important Antarctic pinnipeds. We found that Ross seals forage in an open ocean food web, while crabeater and Weddell seals forage within similar food webs closer to shore. However, isotopic evidence suggests that crabeater seals are likely following sea ice, while Weddell seals target productive areas of the continental shelf of West Antarctica. Our CSI-AA data indicate that Ross seals have a high trophic position equivalent to that of Weddell seals, contrary to prior conclusions from nitrogen isotope results on bulk tissues. CSI-AA indicates that crabeater seals are at a trophic position lower than that of Ross and Weddell seals, consistent with a krill-dominated diet. Our results redefine the view of the trophic dynamics and foraging ecology of the Ross seal, and also highlight the importance of quantifying baseline isotope variations in foraging studies. Article in Journal/Newspaper Antarc* Antarctic Antarctica Crabeater Seal Crabeater Seals Ross Seal Sea ice Weddell Seal Weddell Seals West Antarctica Aarhus University: Research Antarctic Weddell West Antarctica Marine Ecology Progress Series 611 1 18 |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
topic |
Amino acids Antarctica Compound-specific isotopes Crabeater Foraging ecology Ross seal Seal Trophic dynamics Weddell seal WEDDELL SEALS crabeater seal |
spellingShingle |
Amino acids Antarctica Compound-specific isotopes Crabeater Foraging ecology Ross seal Seal Trophic dynamics Weddell seal WEDDELL SEALS crabeater seal Brault, Emily K. Koch, Paul L. Costa, Daniel P. McCarthy, Matthew D. Hückstädt, Luis A. Goetz, Kimberly T. McMahon, Kelton W. Goebel, Michael E. Karlsson, Olle Teilmann, Jonas Harkonen, Tero Harding, Karin C. Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis |
topic_facet |
Amino acids Antarctica Compound-specific isotopes Crabeater Foraging ecology Ross seal Seal Trophic dynamics Weddell seal WEDDELL SEALS crabeater seal |
description |
Ross seals Ommatophoca rossii are one of the least studied marine mammals, with little known about their foraging ecology. Research to date using bulk stable isotope analysis suggests that Ross seals have a trophic position intermediate between that of Weddell Leptonychotes weddellii and crabeater Lobodon carcinophaga seals. However, consumer bulk stable isotope values not only reflect trophic dynamics, but also variations in baseline isotope values, which can be substantial. We used compound-specific isotope analysis of amino acids (CSI-AA) to separate isotopic effects of a shifting baseline versus trophic structure on the foraging ecology of these ecologically important Antarctic pinnipeds. We found that Ross seals forage in an open ocean food web, while crabeater and Weddell seals forage within similar food webs closer to shore. However, isotopic evidence suggests that crabeater seals are likely following sea ice, while Weddell seals target productive areas of the continental shelf of West Antarctica. Our CSI-AA data indicate that Ross seals have a high trophic position equivalent to that of Weddell seals, contrary to prior conclusions from nitrogen isotope results on bulk tissues. CSI-AA indicates that crabeater seals are at a trophic position lower than that of Ross and Weddell seals, consistent with a krill-dominated diet. Our results redefine the view of the trophic dynamics and foraging ecology of the Ross seal, and also highlight the importance of quantifying baseline isotope variations in foraging studies. |
format |
Article in Journal/Newspaper |
author |
Brault, Emily K. Koch, Paul L. Costa, Daniel P. McCarthy, Matthew D. Hückstädt, Luis A. Goetz, Kimberly T. McMahon, Kelton W. Goebel, Michael E. Karlsson, Olle Teilmann, Jonas Harkonen, Tero Harding, Karin C. |
author_facet |
Brault, Emily K. Koch, Paul L. Costa, Daniel P. McCarthy, Matthew D. Hückstädt, Luis A. Goetz, Kimberly T. McMahon, Kelton W. Goebel, Michael E. Karlsson, Olle Teilmann, Jonas Harkonen, Tero Harding, Karin C. |
author_sort |
Brault, Emily K. |
title |
Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis |
title_short |
Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis |
title_full |
Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis |
title_fullStr |
Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis |
title_full_unstemmed |
Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis |
title_sort |
trophic position and foraging ecology of ross, weddell, and crabeater seals revealed by compound-specific isotope analysis |
publishDate |
2019 |
url |
https://pure.au.dk/portal/da/publications/trophic-position-and-foraging-ecology-of-ross-weddell-and-crabeater-seals-revealed-by-compoundspecific-isotope-analysis(7eb6ccb3-e910-49ae-b0cf-c5b9188bb958).html https://doi.org/10.3354/meps12856 https://pure.au.dk/ws/files/194491078/m611p001.pdf http://www.scopus.com/inward/record.url?scp=85061499874&partnerID=8YFLogxK |
geographic |
Antarctic Weddell West Antarctica |
geographic_facet |
Antarctic Weddell West Antarctica |
genre |
Antarc* Antarctic Antarctica Crabeater Seal Crabeater Seals Ross Seal Sea ice Weddell Seal Weddell Seals West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica Crabeater Seal Crabeater Seals Ross Seal Sea ice Weddell Seal Weddell Seals West Antarctica |
op_source |
Brault , E K , Koch , P L , Costa , D P , McCarthy , M D , Hückstädt , L A , Goetz , K T , McMahon , K W , Goebel , M E , Karlsson , O , Teilmann , J , Harkonen , T & Harding , K C 2019 , ' Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis ' , Marine Ecology Progress Series , vol. 611 , pp. 1-18 . https://doi.org/10.3354/meps12856 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.3354/meps12856 |
container_title |
Marine Ecology Progress Series |
container_volume |
611 |
container_start_page |
1 |
op_container_end_page |
18 |
_version_ |
1766258686608539648 |