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FATHOMING THE GULF STREAM - Nature's Pharmacy and Eyes In The Sea MISSION DISPATCH 12 • 08/30/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Brian Cousin - HARBOR BRANCH Oceanographic Somewhere out there to our east is Amelia Island on the coast of Florida, just north of Jacksonville. Being about 95 miles out, land is over the horizon beyond sight. We began our transit to site 4 late yesterday afternoon, after a day of reduced activity due to weather at site 3 on the Blake Plateau. Rather than waiting out a passing squall before launching the sub, persistent overcast skies, rain and rough seas forced the suspension of diving operations for the entire day. 
In the labs,
Dr. Shirley Pomponi and
John Reed caught up with identifying and cataloging specimens collected
on previous day's
Johnson-Sea-Link II dives, entering data and pictures onto a computer.
Dr. Tammy Frank continued her 24-hour experiment with a benthic crab caught in one of her traps and mounted in the physiological prep, measuring electrical responses to applied frequencies of light. As the transit began, a few anglers took the opportunity to troll over the stern for the catch of the day. Luckily, the ship is well stocked with food, as the anglers stow their rods and reels after not so much as a nibble. Towards day's end we were treated to a magnificent sunset every bit as beautiful and textured as the earlier part of the day had been monochromatically gray-blue. Layers of gold and orange turned a deep red that bathed the ship with warmth and color. Puffy dark clouds drifting too low to be touched by sunlight created an especially three-dimensional seascape. 
Morning came as gray and overcast as yesterday, but with an improved sea-state that allows submersible operations
to resume. Reed and Pomponi are on the bridge early, selecting dive sites as the ship transects over a new bottom.
We have had to redefine site 4 somewhat, as our intended coordinates are now off limits. A few days ago, the Navtex
communications receiver on the bridge spit out a printed message warning of exercises hazardous to surface vessels in
the area of our planned research operations.
We will work a few miles south of what has been dubbed "the box", where naval warfare exercises are presumably taking place.
This section of the Florida-Hatteras slope was explored in 1990 using HARBOR BRANCH's Johnson-Sea-Link I and the Navy's NR-1 nuclear-powered research submersible. C.K. Paull, a geologist with the Monterey Bay Aquarium Research Institute (MBARI) reported numerous coral-capped lithoherms, or pinnacles, often exceeding 40 meters in elevation in depths below 440 meters, beyond the penetration of light. The living coral was determined to be as old as 700 years, with exposed crusts on the flanks of the lithoherms determined to be more than 32,000 years old. Paull further calculated that if the distribution of the coral structures in this area were representative of the sea floor under the Gulf Stream in the Straits of Florida and inner Blake Plateau, there may be as many as 40,000 lithoherms. Further extrapolating the number and average size, these seldom seen coral-bearing structures could cover more than 400 square kilometers, an area considerably larger than the shallow water reefs that flank the Straits of Florida, with which we are so much more familiar. While Paull's account of the area is thorough from a geological perspective, it sheds little light on the diversity and abundance of fauna. This mission will provide for the record a characterization of the biota in this deep coral reef region. 
As Reed checks the fathometer history since our arrival at this site early this morning, he sees a pinnacle that reaches
about 500 feet off the bottom, outside the area observed by C.K. Paull. This unexplored peak will be the site of both
JSL dives today, weather permitting.
The sub is up after dive one, and again the sample buckets are filled. There is a curious looking species of Hexactinellida glass sponge with a long filamentous stem resembling a bundle of fiber optic lines. Video of the site, taken from the Johnson-Sea-Link II reveals a well-covered bottom, with an abundance of Lophelia coral and sponges. Some areas appear to be the most heavily covered we have seen this mission. The second dive is on the same site, but the approach is made from the other direction. Dr. Edie Widder is in the sphere with pilot Don Liberatore. The two collect samples and make video transects of the area. Dr. Widder uses the ISIT camera to record a display of bioluminescence on a growth of bamboo coral. The stimulated site glows with bluish light. 
She is clearly invigorated after the dive. Her Eye-In-the-Sea camera stowed for repair and for the moment not at the
forefront of her thoughts, she has bounced back to explore what the ocean has to offer with the tools she has, and with
the knowledge and enthusiasm for which she is so well known and respected.
"It was a great dive. Lots of critters, really interesting topography and some good luminescence. This is the greatest job. You get to explore all of this and maybe find a cure for cancer. It just doesn't get any better!" After just a day here, though, we are departing this very productive site for another further south, to explore the Lophelia reef off the coast of Cape Canaveral. -Paull, C.K., A. C. Neumann, B.A. am Ende, W. Ussler III, and N.M. Rodriguez. Lithoherms on the Florida-Hatteras Slope, Mar. Geol. 166 (2000) 83-101. 
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