Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front
The feeding ecophysiology of the subtropical euphausiid Euphausia spinifera was investigated in the Indian sector of the Southern Ocean during JanuaryFebruary 1999. Gut pigment levels varied from 1.7 to 40.6 ng chlorophyll a (Chl a) equiv.·individual 1 in adults and from 0.3 to 9.3 ng Chl a equiv....
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Language: | English |
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2001
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Online Access: | http://dx.doi.org/10.1139/f00-241 http://www.nrcresearchpress.com/doi/pdf/10.1139/f00-241 |
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crcansciencepubl:10.1139/f00-241 2023-12-17T10:21:22+01:00 Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front Perissinotto, Renzo Mayzaud, Patrick Labat, Jean-Philippe Razouls, Suzanne 2001 http://dx.doi.org/10.1139/f00-241 http://www.nrcresearchpress.com/doi/pdf/10.1139/f00-241 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 58, issue 2, page 273-281 ISSN 0706-652X 1205-7533 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 2001 crcansciencepubl https://doi.org/10.1139/f00-241 2023-11-19T13:39:12Z The feeding ecophysiology of the subtropical euphausiid Euphausia spinifera was investigated in the Indian sector of the Southern Ocean during JanuaryFebruary 1999. Gut pigment levels varied from 1.7 to 40.6 ng chlorophyll a (Chl a) equiv.·individual 1 in adults and from 0.3 to 9.3 ng Chl a equiv.·individual 1 in juveniles. Highest levels were observed at the Subtropical Convergence (Chl a concentrations 0.40.6 µg·L 1 ) and minima in the area north of the Agulhas Front (Chl a concentrations 0.20.3 µg·L 1 ). Gut evacuation rates ranged between 0.59 and 0.96·h 1 . Gut pigment destruction levels were among the highest ever recorded in euphausiids, with 94.298.5% of total pigments ingested converted to nonfluorescing end products. Size-selectivity experiments with natural phytoplankton showed that E. spinifera ingests mainly cells in the 0.7- to 20-µm range. The grazing dynamics of this important species are compared with those of subantarctic (Euphausia vallentini) and Antarctic krill (Euphausia superba). Individual ingestion rates, estimated from the autotrophic component of its diet (2.784.46 µg Chl a equiv.·individual 1 ·day 1 ), were just sufficient to account for respiratory requirements. While E. spinifera is clearly able to ingest large amounts of heterotrophic prey, it is not known to what extent these contribute to its total energy budget. Article in Journal/Newspaper Antarc* Antarctic Antarctic Krill Euphausia superba Southern Ocean Canadian Science Publishing (via Crossref) Antarctic Southern Ocean Indian Canadian Journal of Fisheries and Aquatic Sciences 58 2 273 281 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Aquatic Science Ecology, Evolution, Behavior and Systematics Perissinotto, Renzo Mayzaud, Patrick Labat, Jean-Philippe Razouls, Suzanne Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
The feeding ecophysiology of the subtropical euphausiid Euphausia spinifera was investigated in the Indian sector of the Southern Ocean during JanuaryFebruary 1999. Gut pigment levels varied from 1.7 to 40.6 ng chlorophyll a (Chl a) equiv.·individual 1 in adults and from 0.3 to 9.3 ng Chl a equiv.·individual 1 in juveniles. Highest levels were observed at the Subtropical Convergence (Chl a concentrations 0.40.6 µg·L 1 ) and minima in the area north of the Agulhas Front (Chl a concentrations 0.20.3 µg·L 1 ). Gut evacuation rates ranged between 0.59 and 0.96·h 1 . Gut pigment destruction levels were among the highest ever recorded in euphausiids, with 94.298.5% of total pigments ingested converted to nonfluorescing end products. Size-selectivity experiments with natural phytoplankton showed that E. spinifera ingests mainly cells in the 0.7- to 20-µm range. The grazing dynamics of this important species are compared with those of subantarctic (Euphausia vallentini) and Antarctic krill (Euphausia superba). Individual ingestion rates, estimated from the autotrophic component of its diet (2.784.46 µg Chl a equiv.·individual 1 ·day 1 ), were just sufficient to account for respiratory requirements. While E. spinifera is clearly able to ingest large amounts of heterotrophic prey, it is not known to what extent these contribute to its total energy budget. |
format |
Article in Journal/Newspaper |
author |
Perissinotto, Renzo Mayzaud, Patrick Labat, Jean-Philippe Razouls, Suzanne |
author_facet |
Perissinotto, Renzo Mayzaud, Patrick Labat, Jean-Philippe Razouls, Suzanne |
author_sort |
Perissinotto, Renzo |
title |
Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front |
title_short |
Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front |
title_full |
Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front |
title_fullStr |
Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front |
title_full_unstemmed |
Grazing dynamics of Euphausia spinifera in the region of the Subtropical Convergence and the Agulhas Front |
title_sort |
grazing dynamics of euphausia spinifera in the region of the subtropical convergence and the agulhas front |
publisher |
Canadian Science Publishing |
publishDate |
2001 |
url |
http://dx.doi.org/10.1139/f00-241 http://www.nrcresearchpress.com/doi/pdf/10.1139/f00-241 |
geographic |
Antarctic Southern Ocean Indian |
geographic_facet |
Antarctic Southern Ocean Indian |
genre |
Antarc* Antarctic Antarctic Krill Euphausia superba Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Krill Euphausia superba Southern Ocean |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 58, issue 2, page 273-281 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f00-241 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
58 |
container_issue |
2 |
container_start_page |
273 |
op_container_end_page |
281 |
_version_ |
1785533437913858048 |