The influence of climate variability on zooplankton abundance in the Northern Baltic Archipelago Sea (SW Finland)

Mesozooplankton data were: collected monthly from 1966 to 1984 in the North ern Baltic Archipelago Sea. Interannual variability of the abundance of dif ferent species were related to climate variability using a multivariate reg ression model. The results suggest that in the Archipelago Sea the interannual variability juring spring and summertime of small zooplankton species such as Acartia spp, and Eurytemora affinis is controlled by the climate variability during winter time. No correlations with large scale climate patterns have been d etected for the abundance of larger zooplankton, which seems to be controll ed by the grazing pressure of herring. A significantly high correlation bet ween the anomalies of recruitment of spring herring and the copepodites of Pseudocalanus minutus elongatus indicates the top-down control for this zoo plankton species. (C) 2001 International Council for the Exploration of the Sea.