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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