INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA
A bstract The incidental catch of northern sea lions ( Eumetopias jubatus ) in the walleye pollock ( Theragra chalcogramma ) joint‐venture fishery in Shelikof Strait, Alaska, was studied during 1982–1984 to assess the nature and magnitude of the catch. Data were obtained by placing U.S. observers on...
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Wiley
1986
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crwiley:10.1111/j.1748-7692.1986.tb00025.x 2023-12-03T10:31:12+01:00 INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA Loughlin, Thomas R. Nelson, Russell 1986 http://dx.doi.org/10.1111/j.1748-7692.1986.tb00025.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1748-7692.1986.tb00025.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1748-7692.1986.tb00025.x en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Marine Mammal Science volume 2, issue 1, page 14-33 ISSN 0824-0469 1748-7692 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 1986 crwiley https://doi.org/10.1111/j.1748-7692.1986.tb00025.x 2023-11-09T14:28:51Z A bstract The incidental catch of northern sea lions ( Eumetopias jubatus ) in the walleye pollock ( Theragra chalcogramma ) joint‐venture fishery in Shelikof Strait, Alaska, was studied during 1982–1984 to assess the nature and magnitude of the catch. Data were obtained by placing U.S. observers on foreign processing vessels. Dead sea lions recovered from trawl nets were counted, sexed and measured, teeth were removed for age determination by dental laminae; and stomach contents were analyzed. Although the fishery has continued to expand both in number of boats and estimated total catch (74,136 metric tons [t] in 1982 to 171,539 t in 1984), the estimated incidental catch of northern sea lions has declined (ranging from 958 to 1,436 in 1982, 216 to 324 in 1983 and 237 to 355 in 1984). Of the sea lions processed, 73 percent were caught between 2000 and 0500 h, probably during net retrieval. Most caught sea lions were females ranging in age from 1–25 yr with a mean age of 6.43 yr; 79 percent of the females were sexually mature and probably part of the reproducing population. Males had a mean age of 4.8 yr and only 12 percent were old enough to obtain and defend territories. Analysis of stomach contents showed that the sea lions consumed pollock the same size as that taken by the commercial fishery. The impact of the incidental catch on the Gulf of Alaska sea lion population is unknown. Article in Journal/Newspaper Theragra chalcogramma Alaska Wiley Online Library (via Crossref) Gulf of Alaska Marine Mammal Science 2 1 14 33 |
institution |
Open Polar |
collection |
Wiley Online Library (via Crossref) |
op_collection_id |
crwiley |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Aquatic Science Ecology, Evolution, Behavior and Systematics Loughlin, Thomas R. Nelson, Russell INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
A bstract The incidental catch of northern sea lions ( Eumetopias jubatus ) in the walleye pollock ( Theragra chalcogramma ) joint‐venture fishery in Shelikof Strait, Alaska, was studied during 1982–1984 to assess the nature and magnitude of the catch. Data were obtained by placing U.S. observers on foreign processing vessels. Dead sea lions recovered from trawl nets were counted, sexed and measured, teeth were removed for age determination by dental laminae; and stomach contents were analyzed. Although the fishery has continued to expand both in number of boats and estimated total catch (74,136 metric tons [t] in 1982 to 171,539 t in 1984), the estimated incidental catch of northern sea lions has declined (ranging from 958 to 1,436 in 1982, 216 to 324 in 1983 and 237 to 355 in 1984). Of the sea lions processed, 73 percent were caught between 2000 and 0500 h, probably during net retrieval. Most caught sea lions were females ranging in age from 1–25 yr with a mean age of 6.43 yr; 79 percent of the females were sexually mature and probably part of the reproducing population. Males had a mean age of 4.8 yr and only 12 percent were old enough to obtain and defend territories. Analysis of stomach contents showed that the sea lions consumed pollock the same size as that taken by the commercial fishery. The impact of the incidental catch on the Gulf of Alaska sea lion population is unknown. |
format |
Article in Journal/Newspaper |
author |
Loughlin, Thomas R. Nelson, Russell |
author_facet |
Loughlin, Thomas R. Nelson, Russell |
author_sort |
Loughlin, Thomas R. |
title |
INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA |
title_short |
INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA |
title_full |
INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA |
title_fullStr |
INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA |
title_full_unstemmed |
INCIDENTAL MORTALITY OF NORTHERN SEA LIONS IN SHELIKOF STRAIT, ALASKA |
title_sort |
incidental mortality of northern sea lions in shelikof strait, alaska |
publisher |
Wiley |
publishDate |
1986 |
url |
http://dx.doi.org/10.1111/j.1748-7692.1986.tb00025.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1748-7692.1986.tb00025.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1748-7692.1986.tb00025.x |
geographic |
Gulf of Alaska |
geographic_facet |
Gulf of Alaska |
genre |
Theragra chalcogramma Alaska |
genre_facet |
Theragra chalcogramma Alaska |
op_source |
Marine Mammal Science volume 2, issue 1, page 14-33 ISSN 0824-0469 1748-7692 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/j.1748-7692.1986.tb00025.x |
container_title |
Marine Mammal Science |
container_volume |
2 |
container_issue |
1 |
container_start_page |
14 |
op_container_end_page |
33 |
_version_ |
1784257409616707584 |