Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent
ABSTRACT: The ability of Antarctic krill Euphausia superba Dana to withstand the overwintering period is critical to their success. Laboratory evidence suggests that krill may shrink in body length during this time in response to the low availability of food. Nevertheless, verification that krill ca...
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ftplymouthml:oai:plymsea.ac.uk:7091 2023-05-15T13:57:46+02:00 Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent Tarling, GA Hill, SL Peat, H Fielding, S Reiss C, c Atkinson, A 2016-04-07 text http://plymsea.ac.uk/id/eprint/7091/ http://plymsea.ac.uk/id/eprint/7091/1/Tarling%20et%20al%20MEPS_2016.pdf https://doi.org/10.3354/meps11634 en eng Inter-Research http://plymsea.ac.uk/id/eprint/7091/1/Tarling%20et%20al%20MEPS_2016.pdf Tarling, GA; Hill, SL; Peat, H; Fielding, S; Reiss C, c; Atkinson, A. 2016 Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent. Marine Ecology Progress Series, 547. 61-78. https://doi.org/10.3354/meps11634 <https://doi.org/10.3354/meps11634> cc_by_nd CC-BY-ND Ecology and Environment Fisheries Publication - Article PeerReviewed 2016 ftplymouthml https://doi.org/10.3354/meps11634 2022-09-13T05:48:52Z ABSTRACT: The ability of Antarctic krill Euphausia superba Dana to withstand the overwintering period is critical to their success. Laboratory evidence suggests that krill may shrink in body length during this time in response to the low availability of food. Nevertheless, verification that krill can shrink in the natural environment is lacking because winter data are difficult to obtain. One of the few sources of winter krill population data is from commercial vessels. We examined length-frequency data of adult krill (>35 mm total body length) obtained from commercial vessels in the Scotia-Weddell region and compared our results with those obtained from a combination of science and commercial sampling operations carried out in this region at other times of the year. Our analyses revealed body-length shrinkage in adult females but not males during overwinter, based on both the tracking of modal size classes over seasons and sex-ratio patterns. Other explanatory factors, such as differential mortality, immigration and emigration, could not explain the observed differences. The same pattern was also observed at South Georgia and in the Western Antarctic Peninsula. Fitted seasonally modulated von Bertalanffy growth functions predicted a pattern of overwintering shrinkage in all body-length classes of females, but only stagnation in growth in males. This shrinkage most likely reflects morphometric changes resulting from the contraction of the ovaries and is not necessarily an outcome of winter hardship. The sex-dependent changes that we observed need to be incorporated into life cycle and population dynamic models of this species, particularly those used in managing the fishery. KEY WORDS: Southern Ocean · Population dynamics · Production · Life cycle · Fishery Article in Journal/Newspaper Antarc* Antarctic Antarctic Krill Antarctic Peninsula Euphausia superba Southern Ocean Plymouth Marine Science Electronic Archive (PlyMSEA - Plymouth Marine Laboratory, PML) Antarctic Antarctic Peninsula Southern Ocean Weddell Marine Ecology Progress Series 547 61 78 |
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Open Polar |
collection |
Plymouth Marine Science Electronic Archive (PlyMSEA - Plymouth Marine Laboratory, PML) |
op_collection_id |
ftplymouthml |
language |
English |
topic |
Ecology and Environment Fisheries |
spellingShingle |
Ecology and Environment Fisheries Tarling, GA Hill, SL Peat, H Fielding, S Reiss C, c Atkinson, A Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent |
topic_facet |
Ecology and Environment Fisheries |
description |
ABSTRACT: The ability of Antarctic krill Euphausia superba Dana to withstand the overwintering period is critical to their success. Laboratory evidence suggests that krill may shrink in body length during this time in response to the low availability of food. Nevertheless, verification that krill can shrink in the natural environment is lacking because winter data are difficult to obtain. One of the few sources of winter krill population data is from commercial vessels. We examined length-frequency data of adult krill (>35 mm total body length) obtained from commercial vessels in the Scotia-Weddell region and compared our results with those obtained from a combination of science and commercial sampling operations carried out in this region at other times of the year. Our analyses revealed body-length shrinkage in adult females but not males during overwinter, based on both the tracking of modal size classes over seasons and sex-ratio patterns. Other explanatory factors, such as differential mortality, immigration and emigration, could not explain the observed differences. The same pattern was also observed at South Georgia and in the Western Antarctic Peninsula. Fitted seasonally modulated von Bertalanffy growth functions predicted a pattern of overwintering shrinkage in all body-length classes of females, but only stagnation in growth in males. This shrinkage most likely reflects morphometric changes resulting from the contraction of the ovaries and is not necessarily an outcome of winter hardship. The sex-dependent changes that we observed need to be incorporated into life cycle and population dynamic models of this species, particularly those used in managing the fishery. KEY WORDS: Southern Ocean · Population dynamics · Production · Life cycle · Fishery |
format |
Article in Journal/Newspaper |
author |
Tarling, GA Hill, SL Peat, H Fielding, S Reiss C, c Atkinson, A |
author_facet |
Tarling, GA Hill, SL Peat, H Fielding, S Reiss C, c Atkinson, A |
author_sort |
Tarling, GA |
title |
Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent |
title_short |
Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent |
title_full |
Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent |
title_fullStr |
Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent |
title_full_unstemmed |
Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent |
title_sort |
growth and shrinkage in antarctic krill euphausia superba is sex-dependent |
publisher |
Inter-Research |
publishDate |
2016 |
url |
http://plymsea.ac.uk/id/eprint/7091/ http://plymsea.ac.uk/id/eprint/7091/1/Tarling%20et%20al%20MEPS_2016.pdf https://doi.org/10.3354/meps11634 |
geographic |
Antarctic Antarctic Peninsula Southern Ocean Weddell |
geographic_facet |
Antarctic Antarctic Peninsula Southern Ocean Weddell |
genre |
Antarc* Antarctic Antarctic Krill Antarctic Peninsula Euphausia superba Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Krill Antarctic Peninsula Euphausia superba Southern Ocean |
op_relation |
http://plymsea.ac.uk/id/eprint/7091/1/Tarling%20et%20al%20MEPS_2016.pdf Tarling, GA; Hill, SL; Peat, H; Fielding, S; Reiss C, c; Atkinson, A. 2016 Growth and shrinkage in Antarctic krill Euphausia superba is sex-dependent. Marine Ecology Progress Series, 547. 61-78. https://doi.org/10.3354/meps11634 <https://doi.org/10.3354/meps11634> |
op_rights |
cc_by_nd |
op_rightsnorm |
CC-BY-ND |
op_doi |
https://doi.org/10.3354/meps11634 |
container_title |
Marine Ecology Progress Series |
container_volume |
547 |
container_start_page |
61 |
op_container_end_page |
78 |
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1766265652770766848 |