Zooplankton razing Rates - Experiments conducted aboard the Umitaka-Maru, 2015

The dataset was developed during a cruise on the Umitaka-maru along the 110 E meridian from Fremantle to the ice edge. At five stations, zooplankton were collected and specimens selected for grazing experiments. They were added to 2L bottles, allowed to acclimate over 24 hours then placed in an onboard incubator and allowed to graze on natural phytoplankton assemblages. Water circulation around the incubator kept the temperature to that of seawater at the time of collection. Shade cloth was used to mimic the light conditions at each site. Where possible 4 replicates were run for each species and 4 control bottles were set up with the same phytoplankton assemblage but with no zooplankton added. Initial subsamples were taken and preserved in Lugol's solution. At the end of each experiment, further subsamples were taken and preserved in Lugol's solution. In the IMAS lab the phytoplankton samples were settled into smaller volumes and processed through a Coulter Counter to obtain the number of cells that had been removed by the plankton (initial conc - final conc). From those values, grazing rates of the species could be calculated for each site along the transect.