Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris
Little is known about the foraging behavior of top predators in the deep mesopelagic ocean. Elephant seals dive to the deep biota‐poor oxygen minimum zone (OMZ) (>800 m depth) despite high diving costs in terms of energy and time, but how they successfully forage in the OMZ remains largely unknow...
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ftpubmed:oai:pubmedcentral.nih.gov:5574793 2023-05-15T16:05:36+02:00 Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris Naito, Yasuhiko Costa, Daniel P. Adachi, Taiki Robinson, Patrick W. Peterson, Sarah H. Mitani, Yoko Takahashi, Akinori 2017-07-03 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5574793/ https://doi.org/10.1002/ece3.3202 en eng John Wiley and Sons Inc. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5574793/ http://dx.doi.org/10.1002/ece3.3202 © 2017 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution (http://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. CC-BY Original Research Text 2017 ftpubmed https://doi.org/10.1002/ece3.3202 2017-09-03T00:30:55Z Little is known about the foraging behavior of top predators in the deep mesopelagic ocean. Elephant seals dive to the deep biota‐poor oxygen minimum zone (OMZ) (>800 m depth) despite high diving costs in terms of energy and time, but how they successfully forage in the OMZ remains largely unknown. Assessment of their feeding rate is the key to understanding their foraging behavior, but this has been challenging. Here, we assessed the feeding rate of 14 female northern elephant seals determined by jaw motion events (JME) and dive cycle time to examine how feeding rates varied with dive depth, particularly in the OMZ. We also obtained video footage from seal‐mounted videos to understand their feeding in the OMZ. While the diel vertical migration pattern was apparent for most depths of the JME, some very deep dives, beyond the normal diel depth ranges, occurred episodically during daylight hours. The midmesopelagic zone was the main foraging zone for all seals. Larger seals tended to show smaller numbers of JME and lower feeding rates than smaller seals during migration, suggesting that larger seals tended to feed on larger prey to satisfy their metabolic needs. Larger seals also dived frequently to the deep OMZ, possibly because of a greater diving ability than smaller seals, suggesting their dependency on food in the deeper depth zones. Video observations showed that seals encountered the rarely reported ragfish (Icosteus aenigmaticus) in the depths of the OMZ, which failed to show an escape response from the seals, suggesting that low oxygen concentrations might reduce prey mobility. Less mobile prey in OMZ would enhance the efficiency of foraging in this zone, especially for large seals that can dive deeper and longer. We suggest that the OMZ plays an important role in structuring the mesopelagic ecosystem and for the survival and evolution of elephant seals. Text Elephant Seals PubMed Central (PMC) Ecology and Evolution 7 16 6259 6270 |
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Original Research |
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Original Research Naito, Yasuhiko Costa, Daniel P. Adachi, Taiki Robinson, Patrick W. Peterson, Sarah H. Mitani, Yoko Takahashi, Akinori Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris |
topic_facet |
Original Research |
description |
Little is known about the foraging behavior of top predators in the deep mesopelagic ocean. Elephant seals dive to the deep biota‐poor oxygen minimum zone (OMZ) (>800 m depth) despite high diving costs in terms of energy and time, but how they successfully forage in the OMZ remains largely unknown. Assessment of their feeding rate is the key to understanding their foraging behavior, but this has been challenging. Here, we assessed the feeding rate of 14 female northern elephant seals determined by jaw motion events (JME) and dive cycle time to examine how feeding rates varied with dive depth, particularly in the OMZ. We also obtained video footage from seal‐mounted videos to understand their feeding in the OMZ. While the diel vertical migration pattern was apparent for most depths of the JME, some very deep dives, beyond the normal diel depth ranges, occurred episodically during daylight hours. The midmesopelagic zone was the main foraging zone for all seals. Larger seals tended to show smaller numbers of JME and lower feeding rates than smaller seals during migration, suggesting that larger seals tended to feed on larger prey to satisfy their metabolic needs. Larger seals also dived frequently to the deep OMZ, possibly because of a greater diving ability than smaller seals, suggesting their dependency on food in the deeper depth zones. Video observations showed that seals encountered the rarely reported ragfish (Icosteus aenigmaticus) in the depths of the OMZ, which failed to show an escape response from the seals, suggesting that low oxygen concentrations might reduce prey mobility. Less mobile prey in OMZ would enhance the efficiency of foraging in this zone, especially for large seals that can dive deeper and longer. We suggest that the OMZ plays an important role in structuring the mesopelagic ecosystem and for the survival and evolution of elephant seals. |
format |
Text |
author |
Naito, Yasuhiko Costa, Daniel P. Adachi, Taiki Robinson, Patrick W. Peterson, Sarah H. Mitani, Yoko Takahashi, Akinori |
author_facet |
Naito, Yasuhiko Costa, Daniel P. Adachi, Taiki Robinson, Patrick W. Peterson, Sarah H. Mitani, Yoko Takahashi, Akinori |
author_sort |
Naito, Yasuhiko |
title |
Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris |
title_short |
Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris |
title_full |
Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris |
title_fullStr |
Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris |
title_full_unstemmed |
Oxygen minimum zone: An important oceanographic habitat for deep‐diving northern elephant seals, Mirounga angustirostris |
title_sort |
oxygen minimum zone: an important oceanographic habitat for deep‐diving northern elephant seals, mirounga angustirostris |
publisher |
John Wiley and Sons Inc. |
publishDate |
2017 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5574793/ https://doi.org/10.1002/ece3.3202 |
genre |
Elephant Seals |
genre_facet |
Elephant Seals |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5574793/ http://dx.doi.org/10.1002/ece3.3202 |
op_rights |
© 2017 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution (http://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1002/ece3.3202 |
container_title |
Ecology and Evolution |
container_volume |
7 |
container_issue |
16 |
container_start_page |
6259 |
op_container_end_page |
6270 |
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1766401496044273664 |