Length and age at maturity of Antarctic krill

Data from several summer research cruises in the Antarctic Peninsula region were analysed to calculate length (L 50 ) and age at maturity for the Antarctic krill, Euphausia superba . Length at maturity L 50 is defined as the length at which 50% of the krill stock attains sexual maturity. L 50 values...

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Bibliographic Details
Published in:Antarctic Science
Main Authors: Siegel, V., Loeb, V.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1994
Subjects:
Online Access:http://dx.doi.org/10.1017/s0954102094000726
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102094000726
Description
Summary:Data from several summer research cruises in the Antarctic Peninsula region were analysed to calculate length (L 50 ) and age at maturity for the Antarctic krill, Euphausia superba . Length at maturity L 50 is defined as the length at which 50% of the krill stock attains sexual maturity. L 50 values of 34.65–35.91 mm for female krill are the best estimates for the peak spawning season. Males attain sexual maturity later at L 50 values of 43.35–43.71 mm. Length at maturity and length at first spawning are identical for krill. Comparisons with mean length-at-age data show that females mature in the third growth season (age class 2+), while males reach maturity in the fourth year (age class 3+). Both sexes show ‘knife-edge maturity’.