Moulting interval and growth of juvenile Antarctic krill fed different concentrations of the diatom Phaenodactylum tricornutum in the laboratory
Juvenile Antarctic krill (Euphausia superba) were fed Phaenodactylum tricornutum, at concentrations ranging from 0.0–5.0 mgC 1–1. Intermoult period (IP) decreased, but an increment of body length per moult (∆BL) of juvenile krill increased, up to a concentration of 1.0 mgC 1–1. No further effect of food concentrations on IP or (∆BL was seen at concentration beyond 1.0 mgC 1–1. IP plateaued at 23.8 days and (∆BL, 1.14mm. From these results, maximum daily growth rate (∆BL /IP) of juvenile krill was calculated to be 0.047 mm day–1, which is too slow to support the hypothesised 2-year life-span of this animal in the field. Growth conditions of krill in the Southern Ocean are discussed, with special reference to the available food concentration.
Note: The full text of this paper will be published under the above title in Polar Biology (1987)