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FATHOMING THE GULF STREAM - Nature's Pharmacy and Eyes In The Sea MISSION DISPATCH 6 • 08/24/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Brian Cousin - HARBOR BRANCH Oceanographic Institution Last night the R/V Seward Johnson transited to site 2 of our mission, about 60 nautical miles northwest of our first site on Stetson's Lophelia bank. We are now in comparatively shallow water, 500 to 600 feet deep, on a feature known as the Charleston Bump, which itself contains features known interchangeably as the Charleston Humps and Charleston Lumps. The Bump rises from the western side of the Blake Plateau, from a depth of about 1,000 feet to 500 feet, where it is bounded by the Florida-Hatteras slope. The long, southern flank of the Bump is exposed to the Gulf Stream and the bottom here is described as scoured and eroded. Evidence of Gulf Stream  gyres and eddies can be seen at the surface too, as currents collide, and water deflected
upward by the Bump itself create patches of smooth and rough water at the surface, complete with breaking waves
that suggest shallow offshore reefs.
Into this setting, the Johnson-Sea-Link II makes the first dive of the day. John Reed is in the sphere with pilot Craig Caddigan to collect samples for the Biomedical Marine Research group and two deploy two of Tammy Frank's benthic traps. They are returning to a dive site at the southern end of the Bump visited by Sedberry, in Leg 1 of this Ocean Exploration mission. The sub returns with a number of sponge samples and a couple of odd-looking crustaceans including a crab with very long front appendages that end in rather small claws. Reed, somehow always possessed of the right reference materials, identifies it as belonging to the genus Parthenope. This is as far as he goes. "To determine the species you have to do all kinds of things like count mandible hairs, and such." That's somebody else's field. Tammy Frank is interested in the eyes, though, and grabs her camera to take some digital photos. Then she'll preserve the crab as a teaching specimen. 
In the wet lab, John Reed describes the site: "It was flat, with small rubble on the bottom and low species diversity.
Towards the end of the dive we came across a ridge about 10 feet high that had a little more on it, including a group
of the Parthenope crabs." Wisely, Reed decided against deploying Frank's benthic traps at this site.
With respect to diving in the current, which can flow here with some velocity, Reed says, "To some extent you have to take a chance because the current changes all the time - by the hour, maybe less. We saw a tenth of a knot, two-tenths at most. Sedberry had to abandon a dive here because of strong currents." As the Biomedical Marine Research group continues to process samples from Dive 1, the submersible crew is busy prepping the sub for Dive 2. The charger is connected to the battery and the compressor starts recharging the air tanks that provide ballast to the sub. Dr. Edie Widder's Eye-in-the-Sea camera is secured to the JSL's work platform. Widder successfully re-established data communication between the camera and her computer late yesterday and it is ready to be redeployed. Once on the bottom it will start its time-lapse recording, "blinking" in the darkness for 5 seconds every 10 minutes with its intensified camera eye. 
Edie is pleased with the deployment. "It went smooth as silk. It's in a great place with lots of rocks, lots of life,"
she says. She cycles through the images she shot through the sub's 5 1/4"-thick sphere with her Nikon CoolPix camera.
In addition to shots of the Eye-in-the-Sea positioned nicely on the bottom, there are pictures of a big snowy grouper
swimming right up against the sphere, obviously curious about the visitors to the reef. Dr. Widder laughs, "It was one of
those 'reverse fishbowl' situations - who's watching whom?".
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