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FATHOMING THE GULF STREAM - Nature's Pharmacy and Eyes In The Sea MISSION DISPATCH 4 • 08/22/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Brian Cousin - HARBOR BRANCH Oceanographic Institution Nicolas Joannin has been working as a Research Assistant in the Division of Biomedical Marine Research at HARBOR BRANCH for just 5 months. On this mission of ocean exploration, he is responsible for preserving small pieces of the samples collected on the submersible dives. He's helping to create an 'ark' of sorts-a store of samples that can be accessed later by researchers everywhere. Nicolas graduated in 2000 from the University of Pierre et Marie Curie in Paris, France. Yesterday, he graduated in another way, by joining the ranks of the privileged few to see the ocean floor 2500 feet deep from the Johnson-Sea-Link II. "I knew the space would be small," Nicolas recalls the aft compartment of the sub he occupied on the dive [JSL II dive# 3318 - depth 2008ft.], "but I didn't expect it to be that small. Instruments up front, cushions, a blanket and a fan behind. It's quite small for two adults and I can imagine some people freaking out after awhile at 2,500 feet under water." 
John Reed, Senior Scientist with the Biomedical Marine Research group occupies the decidedly more comfortable forward
sphere of the sub, with pilot Don Liberatore. It's a room with a view-almost 360 degrees, in fact. The objective of
the dive is to collect samples, and to characterize an area of ridges that culminate in a steep, 500 foot pinnacle, as
recorded by the ship's fathometer during the previous evening's transects.
Reed summarizes, "This reef represents one of the tallest deep-water Lophelia coral pinnacles known; nearly 500 feet tall. The lower slope from 2500-2300 feet, is a gentle slope of 10-30 degrees with a series of terraces and ridges that have 100% cover of live and dead coral rubble, and a great diversity of associated fauna. The upper slope, from 2200 to the top at 2050 feet, is steeper, 45-90 degrees, with more exposed rock, and even greater diversity and density of corals, sponges, and gorgonians." Unexpectedly, Spongosorities, the thick, yellow sponge which set a new record of occurrence for the Western Atlantic when seen on an earlier dive, is abundant on the upper slope. Reed continues, "The shallower, upper reaches of the pinnacle are rocky and craggy, 
like a rugged mountaintop. When we reached the top it was a flat plateau. We couldn't see how far it extended before we
ran out of time."
Clearly, the research team is pleasantly surprised by the diversity and the amount of biomass at this site on the Blake Plateau. For Dr. Tammy Frank, however, the water column 600 feet down is less rewarding. Late last night her team deployed the first Tucker trawl of the cruise. After three hours, the sophisticated net with its light-proof cod-end collection container and instrumentation package was recovered and the cod end opened in the ships dark environmental room. Except for a few small amphipods, the long plastic container was empty. This is typical of the comparatively barren Sargassso Sea. Dr. Eric Warrant, the always-cheerful Australian scientist from the University of Lund in Sweden, has dissected the eye of one of the hagfish collected yesterday in Dr. Frank's benthic traps. Now known among his peers aboard ship as "Hagman," Dr. Warrant makes what could be the first report on hagfish eye morphology. "The skin of the head had a light colored window on each side, behind which appeared to be a lens. Besides being very small, each was very much attached to the body wall instead of being free to move about in a socket, making them difficult to extract. The eye didn't appear to be pigmented, usually normal in an eye, and there was probably no retina. Visual pigments detect light and screening pigments give the ability to see spatial detail. That doesn't mean there aren't any photoreceptors,  though it does
indicate a very reduced eye. Can it see? Well, behavioral or electrophysiological studies could indicate that, but it's possible
that the hagfish just relies on other senses. It's a scavenger so it may depend on a sense of smell, or perhaps mechanosensation
like vibration for example."
It's been an eventful day, and not one Nicolas Joannin will soon forget. "The exciting thing for me about the dive was more than what I could see down under. It's the journey in this tiny compartment, this yellow submarine, so to speak. It's going where nobody has ever been ... kind of stretching our limits." That's what exploration is all about. In today's news, the day's first JSL dive to recover Dr. Edie Widder's Eye-in-the-Sea camera was cut short after currents between the surface and the bottom forced the submersible off course. The second dive [JSL II dive# 3319 - depth 2160ft.] was launched just after noon with the primary objective of locating, securing, and recovering the Eye-in-the-Sea camera. On the bridge, Edie joins Jim Sullivan at the comm-track station to monitor the progress on the bottom. The tracking display shows the relative positions of ship, submersible. and targets on the bottom, which are equipped with electronic pingers to indicate their location. The sub icon on the screen, passes near, nearer and directly over the icon representing the camera.  Sub pilot Craig Caddigan radios to the surface that they can't see the camera on the bottom. Another look turns into yet
another look. Chief submersible pilot Don Liberatore joins the group forming around the tracking station. Minutes pass and
the sub icon continues to cross over the camera icon again and again. Liberatore says, "Okay - he's going to say he sees it...
right...right...now!" as it appears on the monitor that the sub is going to run into the camera. The radio remains silent.
Edie is staying cool, smiling a somewhat worried smile. Finally the radio comes to life again, as pilot Caddigan says simply,
"Got it." A quiet cheer goes up on the bridge and Edie looks relieved. In another half hour, the sub and the Eye-in-the-Sea
are safely back on the deck of the
R/V Seward Johnson.
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