Mesozooplankton structure in the northern White Sea in July 2008

The mesozooplankton of the northern White Sea and Mezen Bay was investigated at nine stations in July 2008 using a Juday net (168 mu m mesh size). A total of 39 taxa (species and higher taxa) were found in the samples. Average abundance, biomass, and diversity (Shannon index) were (+/- SE) 120,793 +/- 70,439 ind. m(-2), 443 +/- 216 mg DW m(-2), and 1.41 +/- 0.11, respectively. Copepods were most numerous. Overall, herbivores dominated primarily Cirripedia nauplii and Pseudocalanus minutus. Significant correlations were observed among mean temperature, salinity, and mean mesozooplankton abundance and biomass. Our data suggest that salinity and intensive local currents could be the main factors responsible for the distribution of mesozooplankton in the northern White Sea. The average mesozooplankton biomass was higher than in :previous studies, indicating a possible climatic impact on the mesozooplankton community.