Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder
Antarctic krill (Euphausia superba) aggregate in dense swarms. Previous investigations of krill swarms have used conventional single- or split-beam echosounders that, with post-processing, provide a two-dimensional (2-D) view of the water column, leaving the third dimension to be inferred. We used a...
Published in: | Deep Sea Research Part II: Topical Studies in Oceanography |
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Format: | Article in Journal/Newspaper |
Language: | English |
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2010
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/threedimensional-observations-of-swarms-of-antarctic-krill-euphausia-superba-made-using-a-multibeam-echosounder(23ce04d4-cefa-402c-9474-a73be920befd).html https://doi.org/10.1016/j.dsr2.2009.10.003 http://www.scopus.com/inward/record.url?scp=77949658770&partnerID=8YFLogxK |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/23ce04d4-cefa-402c-9474-a73be920befd 2023-05-15T13:53:11+02:00 Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder Cox, Martin J. Warren, Joseph D. Demer, David A. Cutter, George R. Brierley, Andrew Stuart 2010-04 https://risweb.st-andrews.ac.uk/portal/en/researchoutput/threedimensional-observations-of-swarms-of-antarctic-krill-euphausia-superba-made-using-a-multibeam-echosounder(23ce04d4-cefa-402c-9474-a73be920befd).html https://doi.org/10.1016/j.dsr2.2009.10.003 http://www.scopus.com/inward/record.url?scp=77949658770&partnerID=8YFLogxK eng eng info:eu-repo/semantics/restrictedAccess Cox , M J , Warren , J D , Demer , D A , Cutter , G R & Brierley , A S 2010 , ' Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder ' , Deep Sea Research Part II: Topical Studies in Oceanography , vol. 57 , no. 7-8 , pp. 508-518 . https://doi.org/10.1016/j.dsr2.2009.10.003 Antarctic krill Euphausia superba Pelagic Multibeam echosounder Swarm morphology Three dimensions Livingston Island South Shetland Islands SOUTHERN-OCEAN ACOUSTIC OBSERVATIONS SARDINE SCHOOLS SONAR BEHAVIOR IDENTIFICATION AGGREGATIONS ZOOPLANKTON VARIABILITY PREDATORS article 2010 ftunstandrewcris https://doi.org/10.1016/j.dsr2.2009.10.003 2022-06-02T07:39:48Z Antarctic krill (Euphausia superba) aggregate in dense swarms. Previous investigations of krill swarms have used conventional single- or split-beam echosounders that, with post-processing, provide a two-dimensional (2-D) view of the water column, leaving the third dimension to be inferred. We used a multi-beam echosounder system (SM20, 200 kHz, Kongsberg Mesotech Ltd, Canada) from an inflatable boat (length = 5.5 m) to sample water-column backscatter, particularly krill swarms, directly in 2-D and, with post-processing, to provide a three dimensional (3-D) view of entire krill swarms. The study took place over six days (2-8 February 2006) in the vicinity of Livingston Island, South Shetland Islands, Antarctica (62.4 degrees S, 60.7 degrees W). An automatic 3-D aggregation detection algorithm resolved 1006 krill swarms from the survey data. Principal component analyses indicated that swarm morphology metrics such as length, surface area and volume accounted for the largest between swarm variance, followed by echo energy, and finally swarm geographic location. Swarms did not form basic cylindrical or spherical shapes, but had quite consistent surface area to volume ratios of 3.3 m(-1). Swarms were spatially segregated, with larger sizes (mean north-south length = 276 m, at least double that of two other swarm classifications), found to the northwest of the survey area. The apparent clustering of swarm types suggests that krill biomass surveys and ecosystem investigations may require stratified survey design, in response to varying 3-D swarm morphology, variation that may be driven in turn by environmental characteristics such as bathymetry. (C) 2009 Elsevier Ltd. All rights reserved. Article in Journal/Newspaper Antarc* Antarctic Antarctic Krill Antarctica Euphausia superba Livingston Island South Shetland Islands Southern Ocean University of St Andrews: Research Portal Antarctic Canada Kongsberg ENVELOPE(19.082,19.082,69.123,69.123) Livingston Island ENVELOPE(-60.500,-60.500,-62.600,-62.600) South Shetland Islands Southern Ocean Deep Sea Research Part II: Topical Studies in Oceanography 57 7-8 508 518 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
Antarctic krill Euphausia superba Pelagic Multibeam echosounder Swarm morphology Three dimensions Livingston Island South Shetland Islands SOUTHERN-OCEAN ACOUSTIC OBSERVATIONS SARDINE SCHOOLS SONAR BEHAVIOR IDENTIFICATION AGGREGATIONS ZOOPLANKTON VARIABILITY PREDATORS |
spellingShingle |
Antarctic krill Euphausia superba Pelagic Multibeam echosounder Swarm morphology Three dimensions Livingston Island South Shetland Islands SOUTHERN-OCEAN ACOUSTIC OBSERVATIONS SARDINE SCHOOLS SONAR BEHAVIOR IDENTIFICATION AGGREGATIONS ZOOPLANKTON VARIABILITY PREDATORS Cox, Martin J. Warren, Joseph D. Demer, David A. Cutter, George R. Brierley, Andrew Stuart Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder |
topic_facet |
Antarctic krill Euphausia superba Pelagic Multibeam echosounder Swarm morphology Three dimensions Livingston Island South Shetland Islands SOUTHERN-OCEAN ACOUSTIC OBSERVATIONS SARDINE SCHOOLS SONAR BEHAVIOR IDENTIFICATION AGGREGATIONS ZOOPLANKTON VARIABILITY PREDATORS |
description |
Antarctic krill (Euphausia superba) aggregate in dense swarms. Previous investigations of krill swarms have used conventional single- or split-beam echosounders that, with post-processing, provide a two-dimensional (2-D) view of the water column, leaving the third dimension to be inferred. We used a multi-beam echosounder system (SM20, 200 kHz, Kongsberg Mesotech Ltd, Canada) from an inflatable boat (length = 5.5 m) to sample water-column backscatter, particularly krill swarms, directly in 2-D and, with post-processing, to provide a three dimensional (3-D) view of entire krill swarms. The study took place over six days (2-8 February 2006) in the vicinity of Livingston Island, South Shetland Islands, Antarctica (62.4 degrees S, 60.7 degrees W). An automatic 3-D aggregation detection algorithm resolved 1006 krill swarms from the survey data. Principal component analyses indicated that swarm morphology metrics such as length, surface area and volume accounted for the largest between swarm variance, followed by echo energy, and finally swarm geographic location. Swarms did not form basic cylindrical or spherical shapes, but had quite consistent surface area to volume ratios of 3.3 m(-1). Swarms were spatially segregated, with larger sizes (mean north-south length = 276 m, at least double that of two other swarm classifications), found to the northwest of the survey area. The apparent clustering of swarm types suggests that krill biomass surveys and ecosystem investigations may require stratified survey design, in response to varying 3-D swarm morphology, variation that may be driven in turn by environmental characteristics such as bathymetry. (C) 2009 Elsevier Ltd. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Cox, Martin J. Warren, Joseph D. Demer, David A. Cutter, George R. Brierley, Andrew Stuart |
author_facet |
Cox, Martin J. Warren, Joseph D. Demer, David A. Cutter, George R. Brierley, Andrew Stuart |
author_sort |
Cox, Martin J. |
title |
Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder |
title_short |
Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder |
title_full |
Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder |
title_fullStr |
Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder |
title_full_unstemmed |
Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder |
title_sort |
three-dimensional observations of swarms of antarctic krill (euphausia superba) made using a multi-beam echosounder |
publishDate |
2010 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/threedimensional-observations-of-swarms-of-antarctic-krill-euphausia-superba-made-using-a-multibeam-echosounder(23ce04d4-cefa-402c-9474-a73be920befd).html https://doi.org/10.1016/j.dsr2.2009.10.003 http://www.scopus.com/inward/record.url?scp=77949658770&partnerID=8YFLogxK |
long_lat |
ENVELOPE(19.082,19.082,69.123,69.123) ENVELOPE(-60.500,-60.500,-62.600,-62.600) |
geographic |
Antarctic Canada Kongsberg Livingston Island South Shetland Islands Southern Ocean |
geographic_facet |
Antarctic Canada Kongsberg Livingston Island South Shetland Islands Southern Ocean |
genre |
Antarc* Antarctic Antarctic Krill Antarctica Euphausia superba Livingston Island South Shetland Islands Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Krill Antarctica Euphausia superba Livingston Island South Shetland Islands Southern Ocean |
op_source |
Cox , M J , Warren , J D , Demer , D A , Cutter , G R & Brierley , A S 2010 , ' Three-dimensional observations of swarms of Antarctic krill (Euphausia superba) made using a multi-beam echosounder ' , Deep Sea Research Part II: Topical Studies in Oceanography , vol. 57 , no. 7-8 , pp. 508-518 . https://doi.org/10.1016/j.dsr2.2009.10.003 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.dsr2.2009.10.003 |
container_title |
Deep Sea Research Part II: Topical Studies in Oceanography |
container_volume |
57 |
container_issue |
7-8 |
container_start_page |
508 |
op_container_end_page |
518 |
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1766258153605824512 |