_version_ 1867169497965658112
author Meyer, Bettina
Fuentes, Veronica
Guerra, Citlali
Schmidt, Katrin
Atkinson, Angus
Spahic, Susanne
Cisewski, Boris
Freier, Ulrich
Olariaga, Alejandro
Bathmann, Ulrich
author_facet Meyer, Bettina
Fuentes, Veronica
Guerra, Citlali
Schmidt, Katrin
Atkinson, Angus
Spahic, Susanne
Cisewski, Boris
Freier, Ulrich
Olariaga, Alejandro
Bathmann, Ulrich
collection Datos científicos de ciencias marinas y ambientales
contents The physiological condition of larval Antarctic krill was investigated during austral autumn 2004 and winter 2006 in the Lazarev Sea, to provide better understanding of a critical period of their life cycle. The condition of larvae was quantified in both seasons by determining their body length (BL), dry mass (DM), elemental- and biochemical composition, as well as stomach content analysis, and rates of metabolism and growth. Overall the larvae in autumn were in better condition under the ice than in open water, and for those under the ice there was a decrease in condition from autumn to winter. Thus growth rates of furcilia larvae in open water in autumn were similar to winter values under the ice (mean 0.008 mm/d), whereas autumn, under ice values were higher: 0.015 mm/d. Equivalent larval stages had up to 30% lower BL and 70% lower DM in winter compared to autumn, with mean oxygen consumption 44% lower (0.54 µl O2 DM/h). However, their ammonium excretion rates doubled (from 0.03-0.06 µg NH4 DM/h) so their mean O:N ratio was 46 in autumn and 15 in winter. Thus differing metabolic substrates were used between autumn and winter, suggesting a flexible overwintering strategy, as suggested for adults. The larvae were eating small copepods (Oithona spp.) and/or protozoans as well as autotrophic food under the ice. However, pelagic Chlorophyll a (Chl a) was a good predictor for growth in both seasons. The physics (current speed/ice topography) probably has a critical part to play in whether larval krill can exploit the food that may be associated with sea ice or be advected away from such suitable feeding habitat.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_707193
institution PANGAEA
language en
publishDate 2009
publisher PANGAEA
record_format pangaea
spellingShingle Physiology, growth and development of larval krill ''Euphausia superba'' in autumn and winter in the Lazarev Sea, Antarctica
Meyer, Bettina
Fuentes, Veronica
Guerra, Citlali
Schmidt, Katrin
Atkinson, Angus
Spahic, Susanne
Cisewski, Boris
Freier, Ulrich
Olariaga, Alejandro
Bathmann, Ulrich
ANT-XXI/4; ANT-XXIII/6; AWI_BioOce; Biological Oceanography @ AWI; BONGO; Bongo net; DIVER; Hand net; HN; Polarstern; PS65; PS65/609-4; PS65/612-3; PS65/615-4; PS65/628-7; PS65/661-5; PS65/665-5; PS69; PS69/478-3; PS69/498-A; PS69/498-B; PS69/498-C; PS69/515-A; Sampling by diver
The physiological condition of larval Antarctic krill was investigated during austral autumn 2004 and winter 2006 in the Lazarev Sea, to provide better understanding of a critical period of their life cycle. The condition of larvae was quantified in both seasons by determining their body length (BL), dry mass (DM), elemental- and biochemical composition, as well as stomach content analysis, and rates of metabolism and growth. Overall the larvae in autumn were in better condition under the ice than in open water, and for those under the ice there was a decrease in condition from autumn to winter. Thus growth rates of furcilia larvae in open water in autumn were similar to winter values under the ice (mean 0.008 mm/d), whereas autumn, under ice values were higher: 0.015 mm/d. Equivalent larval stages had up to 30% lower BL and 70% lower DM in winter compared to autumn, with mean oxygen consumption 44% lower (0.54 µl O2 DM/h). However, their ammonium excretion rates doubled (from 0.03-0.06 µg NH4 DM/h) so their mean O:N ratio was 46 in autumn and 15 in winter. Thus differing metabolic substrates were used between autumn and winter, suggesting a flexible overwintering strategy, as suggested for adults. The larvae were eating small copepods (Oithona spp.) and/or protozoans as well as autotrophic food under the ice. However, pelagic Chlorophyll a (Chl a) was a good predictor for growth in both seasons. The physics (current speed/ice topography) probably has a critical part to play in whether larval krill can exploit the food that may be associated with sea ice or be advected away from such suitable feeding habitat.
title Physiology, growth and development of larval krill ''Euphausia superba'' in autumn and winter in the Lazarev Sea, Antarctica
topic ANT-XXI/4; ANT-XXIII/6; AWI_BioOce; Biological Oceanography @ AWI; BONGO; Bongo net; DIVER; Hand net; HN; Polarstern; PS65; PS65/609-4; PS65/612-3; PS65/615-4; PS65/628-7; PS65/661-5; PS65/665-5; PS69; PS69/478-3; PS69/498-A; PS69/498-B; PS69/498-C; PS69/515-A; Sampling by diver
url https://doi.org/10.1594/PANGAEA.707193