Category: Linda Tatreau

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Linda Tatreau, FEBRUARY 13, 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

A HAPPY Valentine’s Day

Deploying the BotCam from a crane
Deploying the BotCam from a crane

The camera team got spectacular results with the BotCam and the BRUVs. I got to watch just a bit of the footage this morning. Everyone is talking about the great shot from the BotCam showing the stern of the ship and the propeller as the camera descends, then fading and picking up the sea floor. (You can see this video clip here.) The BotCam filmed lots of fish and a spotted eagle ray too.

Steve and Sparky preparing the BRUV for deployment.
Steve and Sparky preparing the BRUV for deployment.

The BRUV footage is beautifully clear. I watched only a short section and saw a white tip reef shark, grey reef shark, barracuda, red snapper (Lutjanus bojar), grouper and dogtooth tuna. Also seen were unicornfishes, groupers, Tanguisson wrasses and lots of tangs and butterflyfishes. The depth of the cameras was about 200feet.

Earlier today, the AUV (Autonomous Underwater Vehicle) was deployed. It travels the sea floor following a pre-programmed path for about 4 hours . It keeps itself about 8feet off the bottom. Unfortunately, it was not communicating with the ship, so it had to be retrieved for repairs. In 5 minutes they will deploy the TOAD. I’ll be back. Well, that was great fun and it worked perfectly. The TOAD (Towed Optical Assessment Device) lets us watch the video as the camera is towed above the sea floor. The ship was just drifting at a good speed for the camera. One of the scientists works the controls to keep the TOAD just a few feet off the bottom. This gives great video of the bottom cover, but the fish seem to shy from it. We did see some triggerfishes, jobfishes and a beautiful ray. We spent two hours watching the sea floor starting in an area about 90 feet deep with a lot of coral. We passed through a large sand flat and then dropped off the edge. It got deep so fast that the camera could not be lowered fast enough to keep sight of the bottom. The crew is bringing the TOAD back aboard and soon we will be working with the multibeam sonar to complete the map of Galvez Bank.

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Linda Tatreau, FEBRUARY 12, 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

Sonar and CTD

Jeff & Jonathan prepare the CTD
Retrieving the CTD (check the feet)

All day Friday, all night, and into Saturday has been spent with the multibeam sonar collecting data and mapping the area of study. The “fish people” need an idea of the bottom contours to decide where to put the cameras. Yesterday afternoon, the scientists used a CTD tool to measure conductivity, temperature and density. The results of this test were used by the map makers to most effectively use the sonar data for accurate maps. Currently the camera crew is preparing to launch 5 sets of cameras. The BotCam (bottom camera bait station) has an anchor and floatation that will keep it a few feet above the bottom. The BRUVs (Baited Remote Underwater Video) will sit directly on the bottom. We should have fish data later tonight but, 10 cameras will make a lot of video to watch.

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Linda Tatreau, FEBRUARY 11, 2010

We’re off!

With great anticipation (at least on my part) we departed Guam at 11:30 A.M. Thursday. The scientists have great expectations and most of them matched my excitement. The ship’s crew is mellow – they sail all the time. We went about a mile off shore and spent a few hours while scientists calibrated their equipment. We then went back into Apra Harbor so the multibeam sonar could be calibrated. During the night we actually set sail and are now at Galvez Banks, our first study site. The scientists are continuing their work with the sonar. This will probably take all day today and maybe part of tomorrow. We need the sonar to get good maps of the seafloor so the fish experts can place their gear in the best spots to find fish. We have at least four ways to survey the fish: acoustically, with an AUV (autonomous underwater vehicle), with a towed camera and several rigs that have 2 cameras each and use bait to attract fish. I will share more when the equipment is being used.