Wednesday, May 15, 2013

Port and Plans

On Monday morning we departed for leg 2 of cruise NF1304 after spending a few days in Nassau, Bahamas. It was refreshing to get off the boat and eat local, shop, snorkel, and hang out on the beach for a few days. We hung together as a group for the most part, although various people went SCUBA diving, to the Pirate Museum, or other landmarks on their own. Our science crew also changed during this time, with two researchers leaving and four more coming on. The new group includes two Mexican scientists from ECOSUR and a Spanish scientist from IEO (Instituto Español de Oceanografía), as well as one more hailing from a NOAA lab on the west coast of Florida.

Leg 2 scientists
Most of the science party for leg 2 minus our
lead scientists J. Lamkin, E. Malca, and
S. Privoznik
Leg 1 ended with us having found only two definitive bluefin out of all the tuna larvae we saw. On this leg, we're going to try sampling further north (if you'd like to follow our track, go here). Bluefin tuna spawn in cooler water  near the surface (a shallow thermocline). Often these occur on the edges of cold-core rings (eddies) that form when cold waters upwell, thus creating an independent pocket of rotating cool water that can travel on its own. On leg 1, we sampled waters that remained relatively warm to very deep depths, but we're now journeying north to look for   waters where the cool water is shallow. We have been using a CTD (conductivity-temperature-depth) to monitor conditions.

The common belief held by many tuna scientists and fisheries managers is that bluefin don't spawn in Bahamian waters -- but tagged adult tunas have been known to visit and hang around in this part of the Atlantic without any side trips to either the Mediterranean or the Gulf (the two known spawning grounds). If we find bluefin larvae during this second leg, it would introduce the possibility of bluefin spawning in a third location, thus affecting bluefin fisheries projections. 

We're hoping for better luck this second leg! It's started off with a few equipment issues and some rough seas, but we found the first bluefin of the leg this morning so we're excited for future findings.


Leg 1 stations
All of the stations we completed during leg 1 of our cruise. (To see the entire path, go to the
NOAA ship tracker website).

The science party plus a few others at a local fish fry
The science party, the Foster's two survey techs
and electrical technician, and our hostess at
the local fish fry. 
NOAA ship Nancy Foster at dusk
Our floating hotel docked at the
cruise ship terminal in Nassau.

2 comments:

  1. Awww poor John, misspelled last name ;). But I do really enjoy reading the blog!

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  2. Not anymore! ;) John, Estrella, and Sarah all read this post and none of them picked up on it until you! (nice catch!)

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