Microzooplankton abundance and biomass from CTD bottle samples during the Atlantic Meridional Transect AMT14 cruise in May-June 2004

This dataset contains microzooplankton abundance and biomass data from CTD bottle samples collected during the AMT14 cruise in the Atlantic between Port Stanley, Falkland Islands and the United Kingdom, in May-June 2004. Seawater samples were collected from the CTD Niskin bottles at the pre-dawn cast from up to 4 depths equivalent to 97%, 55%, 14% and 1% surface irradiance. Water samples (1 L in gyre areas and 500 ml in areas of high production) were fixed with 2% Lugol's solution directly from the CTD rosette bottles. 100 ml of the fixed sample was settled for 48 hours prior to examination. The samples were examined using an inverted microscope at x200 magnification to enumerate microzooplankton taxa (>20 µm) (Gifford and Caron, 2000). Estimations of biomass were made after image analysis to estimate standard geometric shapes (Hillebrand et al. , 1999) and by using carbon to volume conversions: pg C cell -1 = 0.22 x (µm 3 ) 0.939 for ciliates and pg C cell -1 = 0.76 x (µm 3 ) 0.819 for dinoflagellates (Menden-Deuer and Lessard, 2000). The data contribute to the AMT project and were collected by scientists from the Plymouth Marine Laboratory.