Wednesday, June 18, 2014

Best offshore Gluten Free Pizza ever........and some pretty good biodiversity too!






Our experience on board the R/V Weatherbird was extremely interesting.  As a group we gathered data and made comparisons between nearshore and offshore sites in the Gulf of Mexico.  We used a CTD to gather water sample data for salinity, temperature, depth, dissolved oxygen, fluorescence and for water chemistry.  For our plankton data we used a neuston net and bongo nets to gather samples.  Our vertebrate and invertebrate samples were gathered with an otter trawl and a benthic dredge. 
Our first site was midday and approximately 18.25 miles southwest of Tampa Bay at a depth of ~23 meters.  At site one my group was responsible for the otter trawl net.  The R/V Weatherbird had a brand new net that had never been used before which may be why our sample size was smaller than previous years.  Our sample site was hard bottom covered by sand and very similar in location to lasts years biodiversity cruise.  We deployed the net as a team and prepared our sampling tables with trays, rulers and scales over the course of 15 minutes while the net was gathering vertebrate and invertebrate data.  After gathering all samples caught in the net we sorted them by similarity and identified nearly all organisms down to genus and species.  We saw a number of flounders, sea robins and jackknife fish that we counted measured and weighed before releasing back into the sea.  We also gathered many echinoderms, sponges, crabs, and other invertebrates.
Our second site was at dusk just outside the Skyway Bridge in Tampa Bay at a depth of ~5 meters.  At site two my group was responsible was the water chemistry data.  We gathered our samples from the CTD team.  We had a total of three samples.  One sample was taken at the surface, one at ~2.5 meters and one at ~5 meters.  I was specifically responsible for salinity, temperature and nitrite content.  In order to gather salinity data I used the refractometer.  The surface salinity was 35 ppt, followed by 36 ppt at ~2.5 meters and 38 ppt near the seafloor.  There were no Nitrites, Nitrates, CO2 or Ammonia present in any of the water samples according to the water chemistry tests.  Our dissolved oxygen and temperature data was gathered by the CTD.  It was interesting to learn all of the techniques involved with gathering all of the chemical data.
Overall the cruise was a success.  The group worked well with each other identifying all organisms.  The chef on board was awesome accommodating my gluten free allergy.  The crew was extremely helpful providing instruction and tours of the ship and the experience as a whole was a great learning resource to understand how biodiversity sampling cruises are done in a scientific way. 

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