An integrated water column sample (12 m) using a weighted hose was collected for phytoplankton speciation and pigment analysis
from February 2010. Prior to this, samples for phytoplankton speciation were collected from 1 m below the surface.
Phytoplankton samples were concentrated by sequential settling over ~ 1 week, reducing the sample down to approximately
15 mL. The final volume was recorded and the sample thoroughly mixed before a 1 mL aliquot was taken and examined by phase
contrast light microscopy (Leica DMLB2) in a Sedgewick-Rafter chamber. The entire chamber was scanned at low power (x50)
to count large or rare species, and then re-examined at x200 until 400 squares had been inspected, or at least 200 cells
of the dominant species had been counted. Thecate dinoflagellates were occasionally examined using fluorescence microscopy
and Calcalfluor to highlight plate structure. The identification of species was confirmed at higher magnification (x400),
and a minimum of 20 squares was examined at x400 to count small flagellates (<5 μm), which were grouped into broad taxonomic
categories based on shape and flagellae.