Plankton relative abundance from net samples and quantitative phytoplankton profiles data collected from R/V Bellows cruise BE-1311 in the Gulf of Mexico from 2012-12-12 to 2012-12-14 (NCEI Accession 0175137)

This dataset reports plankton species abundance from 13 sites off the Florida Panhandle Bight at the head of DeSoto Canyon aboard the R/V Bellows cruise BE-1311 on December 12-14, 2012. Plankton samples were collected using a net with mesh size of 25 micrometer and 0.5m diameter. This dataset reports the location, date, time, and length of tow for each sample. Plankton species were categorized as Ceratium spp., Dinophysis spp., other dinoflagellates, Chaetoceros/Bacteriastrum spp., Rhizosolenia/Guinardia spp, Eucampia/Hemiaulus spp., other chain-forming diatoms, Thalassionematales spp., Nitzschioid diatoms, other diatoms, Cyanobacteria (Trichodesmium spp.), and zooplankton. Abundances were recorded as individual counts as well as percentages of total sample. Quantitative phytoplankton profiles were taken specifically at 4 sites (P1, P3, P5, P7). For this, one-liter samples were collected from the surface and at different depths using Niskin bottles. Samples were filtered onto a 0.45 micrometer nitrocellulose filter and air-dried. A portion of each filter was mounted on an aluminum stub, sputter-coated, and examined with a JEOL JSM-6480 LV scanning electron microscope. Diatoms, coccolithophores, and armored dinoflagellates were identified to the lowest possible taxonomic category. The number of cells of each taxon in a field of view at a magnification of 1000x was recorded, with up to 700 fields-of-view examined, depending on the density of phytoplankton in the sample. The dataset includes the depth, the volume filtered, the number of cells of each taxon counted, and the calculated abundance of each taxon in cells per liter. Micrographs taken during the analysis are included.