Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea
Acoustic estimates of the densities of Antarctic krill, Euphausia superba, in areas around South Georgia (SG) and Elephant Island (EI) were compared for seven austral summers between 1981 and 1997. Estimated densities of krill at SG were most often lower than at EI, although this may simply have bee...
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/concordance-of-interannual-fluctuations-in-acoustically-estimated-densities-of-antarctic-krill-around-south-georgia-and-elephant-islands-biological-evidence-of-sameyear-teleconnections-across-the-scotia-sea(428e213d-6103-4d70-8981-172970c20ebe).html http://www.scopus.com/inward/record.url?scp=0032849459&partnerID=8YFLogxK http://www.link.springer.de |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/428e213d-6103-4d70-8981-172970c20ebe 2023-05-15T13:45:52+02:00 Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea Brierley, Andrew Stuart Demer, DA Watkins, JL Hewitt, R 1999-09 https://risweb.st-andrews.ac.uk/portal/en/researchoutput/concordance-of-interannual-fluctuations-in-acoustically-estimated-densities-of-antarctic-krill-around-south-georgia-and-elephant-islands-biological-evidence-of-sameyear-teleconnections-across-the-scotia-sea(428e213d-6103-4d70-8981-172970c20ebe).html http://www.scopus.com/inward/record.url?scp=0032849459&partnerID=8YFLogxK http://www.link.springer.de eng eng info:eu-repo/semantics/restrictedAccess Brierley , A S , Demer , DA , Watkins , JL & Hewitt , R 1999 , ' Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea ' , Marine Biology , vol. 134 , no. 4 , pp. 675-681 . EUPHAUSIA-SUPERBA DANA FISH STOCKS VARIABILITY RECRUITMENT ABUNDANCE ATLANTIC OCEAN article 1999 ftunstandrewcris 2021-12-26T14:10:06Z Acoustic estimates of the densities of Antarctic krill, Euphausia superba, in areas around South Georgia (SG) and Elephant Island (EI) were compared for seven austral summers between 1981 and 1997. Estimated densities of krill at SG were most often lower than at EI, although this may simply have been a function of differences in the survey and data-analysis techniques used at each site. More interestingly, the magnitudes of density and between-year gradients of density at each site were mirrored by those at the other location; for example 1991 and 1994 were years of very low krill density at both SG and EI. There was no apparent lag in changes in density between sites, and ranked between-year gradients in density at both locations were closely correlated. These pronounced similarities suggest that densities of krill at both locations are linked directly, and may be impacted by the same gross physical and biological factors (e.g. recruitment, dispersal and environmental variability) acting over the same temporal and spatial scales. The observed concordance also implies that the pelagic ecosystems at these widely separated sites (similar or equal to 1500 km distant at opposite sides of the Scotia Sea) are not operating in isolation. Fluctuations in krill density were investigated with reference to cyclical variations in sea ice extent, and in air and sea-surface temperature. The resulting model suggests that the 1999/2000 austral summer will be one of low krill density. Article in Journal/Newspaper Antarc* Antarctic Antarctic Krill Elephant Island Euphausia superba Scotia Sea Sea ice University of St Andrews: Research Portal Antarctic Austral Elephant Island ENVELOPE(-55.184,-55.184,-61.085,-61.085) Scotia Sea |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
EUPHAUSIA-SUPERBA DANA FISH STOCKS VARIABILITY RECRUITMENT ABUNDANCE ATLANTIC OCEAN |
spellingShingle |
EUPHAUSIA-SUPERBA DANA FISH STOCKS VARIABILITY RECRUITMENT ABUNDANCE ATLANTIC OCEAN Brierley, Andrew Stuart Demer, DA Watkins, JL Hewitt, R Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea |
topic_facet |
EUPHAUSIA-SUPERBA DANA FISH STOCKS VARIABILITY RECRUITMENT ABUNDANCE ATLANTIC OCEAN |
description |
Acoustic estimates of the densities of Antarctic krill, Euphausia superba, in areas around South Georgia (SG) and Elephant Island (EI) were compared for seven austral summers between 1981 and 1997. Estimated densities of krill at SG were most often lower than at EI, although this may simply have been a function of differences in the survey and data-analysis techniques used at each site. More interestingly, the magnitudes of density and between-year gradients of density at each site were mirrored by those at the other location; for example 1991 and 1994 were years of very low krill density at both SG and EI. There was no apparent lag in changes in density between sites, and ranked between-year gradients in density at both locations were closely correlated. These pronounced similarities suggest that densities of krill at both locations are linked directly, and may be impacted by the same gross physical and biological factors (e.g. recruitment, dispersal and environmental variability) acting over the same temporal and spatial scales. The observed concordance also implies that the pelagic ecosystems at these widely separated sites (similar or equal to 1500 km distant at opposite sides of the Scotia Sea) are not operating in isolation. Fluctuations in krill density were investigated with reference to cyclical variations in sea ice extent, and in air and sea-surface temperature. The resulting model suggests that the 1999/2000 austral summer will be one of low krill density. |
format |
Article in Journal/Newspaper |
author |
Brierley, Andrew Stuart Demer, DA Watkins, JL Hewitt, R |
author_facet |
Brierley, Andrew Stuart Demer, DA Watkins, JL Hewitt, R |
author_sort |
Brierley, Andrew Stuart |
title |
Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea |
title_short |
Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea |
title_full |
Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea |
title_fullStr |
Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea |
title_full_unstemmed |
Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea |
title_sort |
concordance of interannual fluctuations in acoustically estimated densities of antarctic krill around south georgia and elephant islands; biological evidence of same-year teleconnections across the scotia sea |
publishDate |
1999 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/concordance-of-interannual-fluctuations-in-acoustically-estimated-densities-of-antarctic-krill-around-south-georgia-and-elephant-islands-biological-evidence-of-sameyear-teleconnections-across-the-scotia-sea(428e213d-6103-4d70-8981-172970c20ebe).html http://www.scopus.com/inward/record.url?scp=0032849459&partnerID=8YFLogxK http://www.link.springer.de |
long_lat |
ENVELOPE(-55.184,-55.184,-61.085,-61.085) |
geographic |
Antarctic Austral Elephant Island Scotia Sea |
geographic_facet |
Antarctic Austral Elephant Island Scotia Sea |
genre |
Antarc* Antarctic Antarctic Krill Elephant Island Euphausia superba Scotia Sea Sea ice |
genre_facet |
Antarc* Antarctic Antarctic Krill Elephant Island Euphausia superba Scotia Sea Sea ice |
op_source |
Brierley , A S , Demer , DA , Watkins , JL & Hewitt , R 1999 , ' Concordance of interannual fluctuations in acoustically estimated densities of Antarctic krill around South Georgia and Elephant Islands; biological evidence of same-year teleconnections across the Scotia Sea ' , Marine Biology , vol. 134 , no. 4 , pp. 675-681 . |
op_rights |
info:eu-repo/semantics/restrictedAccess |
_version_ |
1766231717501206528 |