Development and application of an empirical multifrequency method for backscatter classification
We evaluated the feasibility of identifying major acoustic scatters in North Pacific ecosystems based on empirical measurements of relative frequency response. Acoustic measurements in areas where trawl catches were dominated by single taxa indicated that it might be possible to discern among key gr...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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crcansciencepubl:10.1139/f10-075 2024-05-19T07:38:22+00:00 Development and application of an empirical multifrequency method for backscatter classification De Robertis, Alex McKelvey, Denise R. Ressler, Patrick H. Jech, Josef Michael 2010 http://dx.doi.org/10.1139/f10-075 http://www.nrcresearchpress.com/doi/full-xml/10.1139/F10-075 http://www.nrcresearchpress.com/doi/pdf/10.1139/F10-075 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 67, issue 9, page 1459-1474 ISSN 0706-652X 1205-7533 journal-article 2010 crcansciencepubl https://doi.org/10.1139/f10-075 2024-05-02T06:51:25Z We evaluated the feasibility of identifying major acoustic scatters in North Pacific ecosystems based on empirical measurements of relative frequency response. Acoustic measurements in areas where trawl catches were dominated by single taxa indicated that it might be possible to discern among key groups of scatterers such as fish with gas-filled swimbladders, euphausiids, myctophids, and jellyfish. To establish if walleye pollock ( Theragra chalcogramma ), a key species in the ecosystem, can be separated reliably from other groups under prevailing conditions, we developed a method based on the normal deviate (or Z score) to identify backscatter consistent with the pollock relative frequency response. We evaluated the performance of the method by comparing it with the traditional method of species identification (i.e., directed trawl catches and subjective interpretation of echograms) during five large-scale acoustic surveys of the eastern Bering Sea. Pollock abundance estimates employing the multifrequency method were highly correlated with those using the traditional method, which indicates that the multifrequency method performs well in this situation. In this environment, multifrequency methods will allow more inferences to be drawn when direct sampling of organisms is limited and will also complement existing abundance surveys by improving species classification and providing information about key nontarget species. Article in Journal/Newspaper Bering Sea Theragra chalcogramma Canadian Science Publishing Canadian Journal of Fisheries and Aquatic Sciences 67 9 1459 1474 |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
We evaluated the feasibility of identifying major acoustic scatters in North Pacific ecosystems based on empirical measurements of relative frequency response. Acoustic measurements in areas where trawl catches were dominated by single taxa indicated that it might be possible to discern among key groups of scatterers such as fish with gas-filled swimbladders, euphausiids, myctophids, and jellyfish. To establish if walleye pollock ( Theragra chalcogramma ), a key species in the ecosystem, can be separated reliably from other groups under prevailing conditions, we developed a method based on the normal deviate (or Z score) to identify backscatter consistent with the pollock relative frequency response. We evaluated the performance of the method by comparing it with the traditional method of species identification (i.e., directed trawl catches and subjective interpretation of echograms) during five large-scale acoustic surveys of the eastern Bering Sea. Pollock abundance estimates employing the multifrequency method were highly correlated with those using the traditional method, which indicates that the multifrequency method performs well in this situation. In this environment, multifrequency methods will allow more inferences to be drawn when direct sampling of organisms is limited and will also complement existing abundance surveys by improving species classification and providing information about key nontarget species. |
author2 |
Jech, Josef Michael |
format |
Article in Journal/Newspaper |
author |
De Robertis, Alex McKelvey, Denise R. Ressler, Patrick H. |
spellingShingle |
De Robertis, Alex McKelvey, Denise R. Ressler, Patrick H. Development and application of an empirical multifrequency method for backscatter classification |
author_facet |
De Robertis, Alex McKelvey, Denise R. Ressler, Patrick H. |
author_sort |
De Robertis, Alex |
title |
Development and application of an empirical multifrequency method for backscatter classification |
title_short |
Development and application of an empirical multifrequency method for backscatter classification |
title_full |
Development and application of an empirical multifrequency method for backscatter classification |
title_fullStr |
Development and application of an empirical multifrequency method for backscatter classification |
title_full_unstemmed |
Development and application of an empirical multifrequency method for backscatter classification |
title_sort |
development and application of an empirical multifrequency method for backscatter classification |
publisher |
Canadian Science Publishing |
publishDate |
2010 |
url |
http://dx.doi.org/10.1139/f10-075 http://www.nrcresearchpress.com/doi/full-xml/10.1139/F10-075 http://www.nrcresearchpress.com/doi/pdf/10.1139/F10-075 |
genre |
Bering Sea Theragra chalcogramma |
genre_facet |
Bering Sea Theragra chalcogramma |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 67, issue 9, page 1459-1474 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f10-075 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
67 |
container_issue |
9 |
container_start_page |
1459 |
op_container_end_page |
1474 |
_version_ |
1799477811222675456 |