Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula
Ecological relationships of krill and whales have not been explored in the Western Antarctic Peninsula (WAP), and have only rarely been studied elsewhere in the Southern Ocean. In the austral autumn we observed an extremely high density (5.1 whales per km2) of humpback whales (Megaptera novaeangliae...
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ftpubmed:oai:pubmedcentral.nih.gov:3083408 2023-05-15T13:54:36+02:00 Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula Nowacek, Douglas P. Friedlaender, Ari S. Halpin, Patrick N. Hazen, Elliott L. Johnston, David W. Read, Andrew J. Espinasse, Boris Zhou, Meng Zhu, Yiwu 2011-04-27 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3083408 http://www.ncbi.nlm.nih.gov/pubmed/21556153 https://doi.org/10.1371/journal.pone.0019173 en eng Public Library of Science http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3083408 http://www.ncbi.nlm.nih.gov/pubmed/21556153 http://dx.doi.org/10.1371/journal.pone.0019173 Nowacek et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. CC-BY Research Article Text 2011 ftpubmed https://doi.org/10.1371/journal.pone.0019173 2013-09-03T13:53:10Z Ecological relationships of krill and whales have not been explored in the Western Antarctic Peninsula (WAP), and have only rarely been studied elsewhere in the Southern Ocean. In the austral autumn we observed an extremely high density (5.1 whales per km2) of humpback whales (Megaptera novaeangliae) feeding on a super-aggregation of Antarctic krill (Euphausia superba) in Wilhelmina Bay. The krill biomass was approximately 2 million tons, distributed over an area of 100 km2 at densities of up to 2000 individuals m−3; reports of such ‘super-aggregations’ of krill have been absent in the scientific literature for >20 years. Retentive circulation patterns in the Bay entrained phytoplankton and meso-zooplankton that were grazed by the krill. Tagged whales rested during daylight hours and fed intensively throughout the night as krill migrated toward the surface. We infer that the previously unstudied WAP embayments are important foraging areas for whales during autumn and, furthermore, that meso-scale variation in the distribution of whales and their prey are important features of this system. Recent decreases in the abundance of Antarctic krill around the WAP have been linked to reductions in sea ice, mediated by rapid climate change in this area. At the same time, baleen whale populations in the Southern Ocean, which feed primarily on krill, are recovering from past exploitation. Consideration of these features and the effects of climate change on krill dynamics are critical to managing both krill harvests and the recovery of baleen whales in the Southern Ocean. Text Antarc* Antarctic Antarctic Krill Antarctic Peninsula baleen whale baleen whales Euphausia superba Megaptera novaeangliae Sea ice Southern Ocean PubMed Central (PMC) Antarctic Antarctic Peninsula Austral Southern Ocean Wilhelmina ENVELOPE(-62.160,-62.160,-64.642,-64.642) Wilhelmina Bay ENVELOPE(-62.160,-62.160,-64.642,-64.642) PLoS ONE 6 4 e19173 |
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PubMed Central (PMC) |
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Research Article |
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Research Article Nowacek, Douglas P. Friedlaender, Ari S. Halpin, Patrick N. Hazen, Elliott L. Johnston, David W. Read, Andrew J. Espinasse, Boris Zhou, Meng Zhu, Yiwu Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula |
topic_facet |
Research Article |
description |
Ecological relationships of krill and whales have not been explored in the Western Antarctic Peninsula (WAP), and have only rarely been studied elsewhere in the Southern Ocean. In the austral autumn we observed an extremely high density (5.1 whales per km2) of humpback whales (Megaptera novaeangliae) feeding on a super-aggregation of Antarctic krill (Euphausia superba) in Wilhelmina Bay. The krill biomass was approximately 2 million tons, distributed over an area of 100 km2 at densities of up to 2000 individuals m−3; reports of such ‘super-aggregations’ of krill have been absent in the scientific literature for >20 years. Retentive circulation patterns in the Bay entrained phytoplankton and meso-zooplankton that were grazed by the krill. Tagged whales rested during daylight hours and fed intensively throughout the night as krill migrated toward the surface. We infer that the previously unstudied WAP embayments are important foraging areas for whales during autumn and, furthermore, that meso-scale variation in the distribution of whales and their prey are important features of this system. Recent decreases in the abundance of Antarctic krill around the WAP have been linked to reductions in sea ice, mediated by rapid climate change in this area. At the same time, baleen whale populations in the Southern Ocean, which feed primarily on krill, are recovering from past exploitation. Consideration of these features and the effects of climate change on krill dynamics are critical to managing both krill harvests and the recovery of baleen whales in the Southern Ocean. |
format |
Text |
author |
Nowacek, Douglas P. Friedlaender, Ari S. Halpin, Patrick N. Hazen, Elliott L. Johnston, David W. Read, Andrew J. Espinasse, Boris Zhou, Meng Zhu, Yiwu |
author_facet |
Nowacek, Douglas P. Friedlaender, Ari S. Halpin, Patrick N. Hazen, Elliott L. Johnston, David W. Read, Andrew J. Espinasse, Boris Zhou, Meng Zhu, Yiwu |
author_sort |
Nowacek, Douglas P. |
title |
Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula |
title_short |
Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula |
title_full |
Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula |
title_fullStr |
Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula |
title_full_unstemmed |
Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula |
title_sort |
super-aggregations of krill and humpback whales in wilhelmina bay, antarctic peninsula |
publisher |
Public Library of Science |
publishDate |
2011 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3083408 http://www.ncbi.nlm.nih.gov/pubmed/21556153 https://doi.org/10.1371/journal.pone.0019173 |
long_lat |
ENVELOPE(-62.160,-62.160,-64.642,-64.642) ENVELOPE(-62.160,-62.160,-64.642,-64.642) |
geographic |
Antarctic Antarctic Peninsula Austral Southern Ocean Wilhelmina Wilhelmina Bay |
geographic_facet |
Antarctic Antarctic Peninsula Austral Southern Ocean Wilhelmina Wilhelmina Bay |
genre |
Antarc* Antarctic Antarctic Krill Antarctic Peninsula baleen whale baleen whales Euphausia superba Megaptera novaeangliae Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Krill Antarctic Peninsula baleen whale baleen whales Euphausia superba Megaptera novaeangliae Sea ice Southern Ocean |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3083408 http://www.ncbi.nlm.nih.gov/pubmed/21556153 http://dx.doi.org/10.1371/journal.pone.0019173 |
op_rights |
Nowacek et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1371/journal.pone.0019173 |
container_title |
PLoS ONE |
container_volume |
6 |
container_issue |
4 |
container_start_page |
e19173 |
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1766260581828919296 |