Open Access Repository

In situ growth rate estimates of Southern Ocean krill, Thysanoessa macrura

Wallis, JR ORCID: 0000-0003-2932-612X, Melvin, JE, King, R and Kawaguchi, S 2019 , 'In situ growth rate estimates of Southern Ocean krill, Thysanoessa macrura' , Antarctic Science , pp. 1-7 , doi: 10.1017/S0954102019000063.

Full text not available from this repository.


Growth, which is intrinsically linked to environmental conditions including temperature and food availability are highly variable both temporally and spatially. Estimates of growth rates of the Southern Ocean euphausiid Thysanoessa macrura are currently restricted to limited studies which rely upon repeated sampling and length-frequency analysis to quantify growth rates. The instantaneous growth method (IGR) was used to measure the growth rate of T. macrura successfully in the southern Kerulen Plateau region during summer, providing the first IGR parameters for the Southern Ocean euphausiid species. Results of the four-day IGR incubation indicate a period of low somatic growth for adult T. macrura. Males had a longer intermoult period (IMP) (62 days) than females (42 days), but the sexes exhibited similar daily growth rates of 0.011 mm day−1 and 0.012 mm day−1 respectively. Juveniles exhibited the fastest growth, with an IMP of 13 days and daily growth rate of 0.055 mm day−1 indicating a prolonged growth season, similar to the Antarctic krill E. superba. Consequently, we highlight the usability of the IGR method and strongly encourage its use in developing a comprehensive understanding of spatial and seasonal growth patterns of T. macrura.

Item Type: Article
Authors/Creators:Wallis, JR and Melvin, JE and King, R and Kawaguchi, S
Keywords: daily growth rate, krill, Southern Ocean, instantaneous growth rate, intermoult period
Journal or Publication Title: Antarctic Science
Publisher: Cambridge Univ Press
ISSN: 0954-1020
DOI / ID Number: 10.1017/S0954102019000063
Copyright Information:

Copyright 2019 Antarctic Science Ltd

Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page