The energetic cost of egg production in Antarctic krill (<i>Euphausia superba</i> Dana)

Abstract

A female Antarctic krill loses 34% of its body mass when it lays a batch of eggs. This represents a considerable input of energy which was estimated using a combination of measured mass and energy differences in female krill and from the measured energetic content of ovarian tissue. Large ( c. 50 mm) female krill lose 2.9–3.8 kJ each time a batch of eggs is laid. Calculations using this figure indicate that multiple spawning by Antarctic krill in a season would require above average phytoplankton concentrations (&gt; 0.5 μg chl a 1 −1 ) and filtration rates which are close to the maximum reported (&gt; 10 l h −1 ).