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Linda Tatreau, FEBRUARY 22, 2010

NOAA Teacher at Sea: Linda Tatreau
Onboard NOAA Ship Oscar Elton Sette

Mission: Fisheries Surveys
Geographical Area of Cruise: Equatorial Pacific
Date: February 22, 2010

 

Rota

Rota
Rota

This is day #3 working off-shore of the beautiful island of Rota. While working at Galvez Bank we could see Guam at a distance of about 14 miles, but it was just a big bump on the horizon. While working in this location, we are close to shore and can enjoy the view of tropical vegetation, white sandy beaches and carbonate cliffs. The work in Rota has included BRUVs, multibeam and the AUV.

Linda, Viv and Tony with Rota in the background.

The AUV work has gone smoothly. Launching occurs each evening about 8:00 with recovery at midnight. The AUV has 2 cameras, one facing downward to photograph the geography and one facing forward for better fish identification (it’s difficult to identify a fish from the top, looking down). At night the AUV takes only still photographs. A strobe illuminates the scene every 5 seconds and the cameras shoot in synchronicity. A 4-hour trip produces more than 2,500 photographs with each camera. Processing that many pictures is a time consuming job. The AUV also has a CTD and records data for future analysis. Chirs (see Meet the Science Team) is working on a program that will allow the AUV to send pictures to the ship in real time. To date, this has only been accomplished when a ship is directly over the AUV. Chris is very close to success―maybe tonight.

Linda cutting bait for the BRUV bait bags.
BRUV boys loaded up and ready go.
The BRUV team says this trip has been the easiest BRUV work ever. In the next breath, they say this trip has been the most difficult BRUV work ever. The easiest―Galvez Bank where launch and recovery were from the ship. Launching was accomplished by simply tossing them off the stern. They were brought back aboard using an electric winch. The most difficult―Rota where the work is close to shore and the ship can’t go. Now they are using a small boat. With all the equipment piled on the boat, there is barely space for 3 people―the driver and 2 to handle the BRUVs. They have 4 BRUVs nestled on the little boat along with all the associated lines and buoys . Add bait, bait bags, lunch and drink and there is not much working area. Once rigged, the BRUVs are tossed over the side in 100 to 150 feet of water. Recovery is accomplished using a hand winch―at 150 feet deep, that is a lot of manual turns of the handle. Difficult as it may be, yesterday they managed 13 BRUV drops in 8 hours.

OK, every entry in this blog has been mostly science. For me, that’s the greatest fun. For the next entry, I’ll try for some of the non-science fun onboard a ship.

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