Interannual variability of zooplankton biomass and structure in Ría de Vigo ( Galiza, NW Spain) and adjacent shelfwaters between 1994 and 2000.

Abstract

Changes in zooplankton biomass and structure in relation to hidroclimatological indexes in Ría de Vigo and adjacent shelf waters are presented for the period 1994-2000. Zooplankton biomass showed an inverse relation with NAO, the Gulf Current and upwelling indexes. The interannual variations in zooplankton composition showed a gook correlation to changes in the hidroclimatological indexes. The presence of warm water species of Copepoda (i.e., Temora stylifera) and Cladocera (i.e., Evadne spinifera, Penilia avirostris) between 1996 and 1998 is reported. In the same years a high abundance of oceanic copepods, such as: Paraeuchaeta hebes, Centropages chierchiae, Oithona plumifera and copepodits of Calanus helgolandicus have been observed inside Ría de Vigo