Contrasting zooplankton communities (Arctic vs. Atlantic) in the European Arctic Marginal Ice Zone

Relationships between the zooplankton community andv arious environmental factors (salinity, temperature, sampling depth and bottom depth) were established in the European Arctic Marginal Ice Zone (MIZ) using multivariate statistics. Three main zooplankton communities were identified: an Atlantic Shallow Community (AtSC), an Arctic Shallow Community (ArSC) anda Deep Water Community (DWC). All species belonging to AtSC andArSC were pooledandtheir relative abundances in the total zooplankton calculated with respect to a particular layer (surface, midan dd eep strata), regions (the Barents Sea, Fram Strait andt he waters off northern Svalbard), years (1999 or 2003) and seasons (spring or autumn). Mapping of the proportions of Arctic andA tlantic species ledto the conclusion that zooplankton from the MIZs do not exactly follow complementary water masses, although the general pattern of AtSC and ArSC dominance accords with the physical oceanography of the study area (AtW and ArW respectively). The mid layer proved to be a better predictor of mesozooplankton distribution than the unstable conditions near the surface.