Abundance, biomass, composition and grazing impact of the sea-ice meiofauna in the North Water, northern Baffin Bay

The abundance, biomass, composition and grazing impact of the bottom sea-ic e meio-fauna were investigated in the North Water, High Arctic, during Apri l and May 1998. Sampling was conducted on both pack ice and land fast-ice. At the lowermost 2 to 4 cm of the sea ice, chlorophyll a reached a maximum concentration of 55.7 mg m(-2). Sea-ice meiofauna were observed only at the ice bottom, and were composed of nematodes, copepods (harpacticoids and cy clopoids), crustacean nauplii, polychaete larvae and turbellarians. Total a bundance of sea-ice meiofauna ranged from 0 to 34 500 ind. m(-2) at the sam pling stations. Nematodes were the most abundant taxon in the ice, with hig hest densities at a land fast-ice station. Highest abundances of copepods a s well as crustacean nauplii were observed in the pack ice. The total sea-i ce meiofauna biomass varied between 0 and 19.4 Mg C m(-2). Potential ingest ion rates, determined using allometric equations, indicated that sea-ice me iofauna never consumed more than 0.9 % of the ice-algae standing stock and 5.7 % of the daily ice-algae production, These calculations strongly sugges t that the grazing impact of sea-ice meiofauna on ice algae was negligible in the North Water in early spring, The low standing stock of ice meiofauna also precludes their potential as an important food source for higher trop hic levels.Meiofauna, therefore, appear to be a minor contributor to the ov erall carbon flow in the sea-ice biota of the North Water during spring.