RNA concentration in zooplankton: seasonal variation in boreal species

Abstract

Variation in RNA concentration of 18 spp. of macrozooplankton [Calanus hyperboreus, Chiridius armatus, Euchaeta norvegica, Metridia longa, Boreomysis arctica, Meganyctiphanes norvegica, Thysanoessa sp., Parathemisto abyssorum, Pasiphaea multidentata, Eukrohnia hamata, Tomopteris helgolandica, Aglantha digitale, Hemimysis abyssicola, Orchomenopsis obtusa, Clione limacina, Eukrohnia bathypelagica, Sagitta elegans and Pleurobrachia pileus] from the Swedish west coast was followed over an 8-mo. period. There was a general trend of increasing RNA concentration from winter towards summer with maximum values usually occurring from March-June. The main seasonal variation in RNA concentration may reflect the seasonal variation in food supply and peaks to correspond to periods of high breeding intensity in species with discrete reproduction.