Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003
In 2001’003, >60,000 km of aerial surveys and 7,700 km of vessel surveys were conducted during June to November when critically endangered Korean–Okhotsk or western gray whales (Eschrichtius robustus) were present off the northeast coast of Sakhalin Island, Russia. Results of surveys in all years...
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ftpubmed:oai:pubmedcentral.nih.gov:2798039 2023-05-15T18:08:57+02:00 Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 Meier, S. K. Yazvenko, S. B. Blokhin, S. A. Wainwright, P. Maminov, M. K. Yakovlev, Y. M. Newcomer, M. W. 2007-08-17 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2798039 http://www.ncbi.nlm.nih.gov/pubmed/17703367 https://doi.org/10.1007/s10661-007-9811-2 en eng Springer Netherlands http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2798039 http://www.ncbi.nlm.nih.gov/pubmed/17703367 http://dx.doi.org/10.1007/s10661-007-9811-2 © Springer Science+Business Media B.V. 2007 Article Text 2007 ftpubmed https://doi.org/10.1007/s10661-007-9811-2 2013-09-02T20:05:49Z In 2001’003, >60,000 km of aerial surveys and 7,700 km of vessel surveys were conducted during June to November when critically endangered Korean–Okhotsk or western gray whales (Eschrichtius robustus) were present off the northeast coast of Sakhalin Island, Russia. Results of surveys in all years indicated gray whales occurred in predominantly two areas, (1) adjacent to Piltun Bay, and (2) offshore from Chayvo Bay, hereafter referred to as the Piltun and offshore feeding areas. In the Piltun feeding area, the majority of whales were observed in waters shallower than 20 m and were distributed from several hundred meters to ∼ 5 km from the shoreline. In the offshore feeding area during all years, the distribution of gray whales extended from southwest to northeast in waters 30’5 m in depth. During all years, the distribution and abundance of whales changed in both the Piltun and offshore feeding areas, and both north–south and inshore–offshore movements were documented within and between feeding seasons. The discovery of a significant number of whales feeding in the offshore area each year was a substantial finding of this study and raises questions regarding western gray whale abundance and population levels, feeding behavior and ecology, and individual site-fidelity. Fluctuations in the number of whales observed within the Piltun and offshore feeding areas and few sightings outside of these two areas indicate that gray whales move between the Piltun and offshore feeding areas during their summer–fall feeding season. Seasonal shifts in the distribution and abundance of gray whales between and within both the Piltun and offshore feeding areas are thought, in part, to be a response to seasonal changes in the distribution and abundance of prey. However, the mechanism driving the movements of whales along the northeast coast of Sakhalin Island is likely very complex and influenced by a multitude of factors. Text Sakhalin PubMed Central (PMC) Okhotsk Environmental Monitoring and Assessment 134 1-3 107 136 |
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Article Meier, S. K. Yazvenko, S. B. Blokhin, S. A. Wainwright, P. Maminov, M. K. Yakovlev, Y. M. Newcomer, M. W. Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 |
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Article |
description |
In 2001’003, >60,000 km of aerial surveys and 7,700 km of vessel surveys were conducted during June to November when critically endangered Korean–Okhotsk or western gray whales (Eschrichtius robustus) were present off the northeast coast of Sakhalin Island, Russia. Results of surveys in all years indicated gray whales occurred in predominantly two areas, (1) adjacent to Piltun Bay, and (2) offshore from Chayvo Bay, hereafter referred to as the Piltun and offshore feeding areas. In the Piltun feeding area, the majority of whales were observed in waters shallower than 20 m and were distributed from several hundred meters to ∼ 5 km from the shoreline. In the offshore feeding area during all years, the distribution of gray whales extended from southwest to northeast in waters 30’5 m in depth. During all years, the distribution and abundance of whales changed in both the Piltun and offshore feeding areas, and both north–south and inshore–offshore movements were documented within and between feeding seasons. The discovery of a significant number of whales feeding in the offshore area each year was a substantial finding of this study and raises questions regarding western gray whale abundance and population levels, feeding behavior and ecology, and individual site-fidelity. Fluctuations in the number of whales observed within the Piltun and offshore feeding areas and few sightings outside of these two areas indicate that gray whales move between the Piltun and offshore feeding areas during their summer–fall feeding season. Seasonal shifts in the distribution and abundance of gray whales between and within both the Piltun and offshore feeding areas are thought, in part, to be a response to seasonal changes in the distribution and abundance of prey. However, the mechanism driving the movements of whales along the northeast coast of Sakhalin Island is likely very complex and influenced by a multitude of factors. |
format |
Text |
author |
Meier, S. K. Yazvenko, S. B. Blokhin, S. A. Wainwright, P. Maminov, M. K. Yakovlev, Y. M. Newcomer, M. W. |
author_facet |
Meier, S. K. Yazvenko, S. B. Blokhin, S. A. Wainwright, P. Maminov, M. K. Yakovlev, Y. M. Newcomer, M. W. |
author_sort |
Meier, S. K. |
title |
Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 |
title_short |
Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 |
title_full |
Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 |
title_fullStr |
Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 |
title_full_unstemmed |
Distribution and abundance of western gray whales off northeastern Sakhalin Island, Russia, 2001’003 |
title_sort |
distribution and abundance of western gray whales off northeastern sakhalin island, russia, 2001’003 |
publisher |
Springer Netherlands |
publishDate |
2007 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2798039 http://www.ncbi.nlm.nih.gov/pubmed/17703367 https://doi.org/10.1007/s10661-007-9811-2 |
geographic |
Okhotsk |
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Okhotsk |
genre |
Sakhalin |
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Sakhalin |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2798039 http://www.ncbi.nlm.nih.gov/pubmed/17703367 http://dx.doi.org/10.1007/s10661-007-9811-2 |
op_rights |
© Springer Science+Business Media B.V. 2007 |
op_doi |
https://doi.org/10.1007/s10661-007-9811-2 |
container_title |
Environmental Monitoring and Assessment |
container_volume |
134 |
container_issue |
1-3 |
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107 |
op_container_end_page |
136 |
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1766181344958742528 |