Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors
Generalized additive models (GAM), a nonparametric regression method with less restrictive statistical assumptions than traditional regression methods, were used to model the trend in mean abundance of Bering Sea walleye pollock (Theragra chalcogramma) as a function of ocean environmental conditions...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Canadian Science Publishing
1995
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Online Access: | http://dx.doi.org/10.1139/f95-039 http://www.nrcresearchpress.com/doi/pdf/10.1139/f95-039 |
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crcansciencepubl:10.1139/f95-039 2024-09-15T17:59:26+00:00 Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors Swartzman, Gordon Silverman, Emily Williamson, Neal 1995 http://dx.doi.org/10.1139/f95-039 http://www.nrcresearchpress.com/doi/pdf/10.1139/f95-039 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 52, issue 2, page 369-380 ISSN 0706-652X 1205-7533 journal-article 1995 crcansciencepubl https://doi.org/10.1139/f95-039 2024-08-29T04:08:49Z Generalized additive models (GAM), a nonparametric regression method with less restrictive statistical assumptions than traditional regression methods, were used to model the trend in mean abundance of Bering Sea walleye pollock (Theragra chalcogramma) as a function of ocean environmental conditions including water column depth, temperature at 50 m, and depth of the thermocline. Acoustic survey data collected in the summers of 1988 and 1991 were used to test these relationships. In both surveys, mean walleye pollock abundance was highest in areas having a 70–130 m depth range and where the 50-m temperature was close to 2.5 °C. Thermocline depth, while not itself significant, had a significant effect on walleye pollock abundance through interactions with both bottom depth and temperature at 50 m. Walleye pollock in the top 50 m of the water column (mostly juveniles) were influenced differently by temperature and thermocline depth than the adult walleye pollock, which were generally deeper in the water column. The depth, temperature, and thermocline preferences of walleye pollock are hypothesized to be linked to food availability which is, in turn, related to temperature regimes or fronts along the Bering Sea shelf slope. Article in Journal/Newspaper Bering Sea Theragra chalcogramma Canadian Science Publishing Canadian Journal of Fisheries and Aquatic Sciences 52 2 369 380 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
Generalized additive models (GAM), a nonparametric regression method with less restrictive statistical assumptions than traditional regression methods, were used to model the trend in mean abundance of Bering Sea walleye pollock (Theragra chalcogramma) as a function of ocean environmental conditions including water column depth, temperature at 50 m, and depth of the thermocline. Acoustic survey data collected in the summers of 1988 and 1991 were used to test these relationships. In both surveys, mean walleye pollock abundance was highest in areas having a 70–130 m depth range and where the 50-m temperature was close to 2.5 °C. Thermocline depth, while not itself significant, had a significant effect on walleye pollock abundance through interactions with both bottom depth and temperature at 50 m. Walleye pollock in the top 50 m of the water column (mostly juveniles) were influenced differently by temperature and thermocline depth than the adult walleye pollock, which were generally deeper in the water column. The depth, temperature, and thermocline preferences of walleye pollock are hypothesized to be linked to food availability which is, in turn, related to temperature regimes or fronts along the Bering Sea shelf slope. |
format |
Article in Journal/Newspaper |
author |
Swartzman, Gordon Silverman, Emily Williamson, Neal |
spellingShingle |
Swartzman, Gordon Silverman, Emily Williamson, Neal Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors |
author_facet |
Swartzman, Gordon Silverman, Emily Williamson, Neal |
author_sort |
Swartzman, Gordon |
title |
Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors |
title_short |
Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors |
title_full |
Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors |
title_fullStr |
Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors |
title_full_unstemmed |
Relating trends in walleye pollock ( Theragra chalcogramma) abundance in the Bering Sea to environmental factors |
title_sort |
relating trends in walleye pollock ( theragra chalcogramma) abundance in the bering sea to environmental factors |
publisher |
Canadian Science Publishing |
publishDate |
1995 |
url |
http://dx.doi.org/10.1139/f95-039 http://www.nrcresearchpress.com/doi/pdf/10.1139/f95-039 |
genre |
Bering Sea Theragra chalcogramma |
genre_facet |
Bering Sea Theragra chalcogramma |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 52, issue 2, page 369-380 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f95-039 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
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52 |
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2 |
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369 |
op_container_end_page |
380 |
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1810436521301377024 |