Physiology, growth and development of larval krill ''Euphausia superba'' in autumn and winter in the Lazarev Sea, Antarctica

DOI

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.

Supplement to: Meyer, Bettina; Fuentes, Veronica; Guerra, Citlali; Schmidt, Katrin; Atkinson, Angus; Spahic, Susanne; Cisewski, Boris; Freier, Ulrich; Olariaga, Alejandro; Bathmann, Ulrich (2009): Physiology, growth and development of larval krill ''Euphausia superba'' in autumn and winter in the Lazarev Sea, Antarctica. Limnology and Oceanography, 54(5)

Identifier
DOI https://doi.org/10.1594/PANGAEA.707193
Related Identifier IsSupplementTo https://doi.org/10.4319/lo.2009.54.5.1595
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.707193
Provenance
Creator Meyer, Bettina ORCID logo; Fuentes, Veronica; Guerra, Citlali; Schmidt, Katrin (ORCID: 0000-0002-6488-623X); Atkinson, Angus; Spahic, Susanne; Cisewski, Boris ORCID logo; Freier, Ulrich; Olariaga, Alejandro; Bathmann, Ulrich
Publisher PANGAEA
Publication Year 2009
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 33 datasets
Discipline Earth System Research
Spatial Coverage (-6.000W, -69.621S, 2.955E, -63.453N)
Temporal Coverage Begin 2004-04-07T22:04:00Z
Temporal Coverage End 2006-08-02T15:00:00Z