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FATHOMING THE GULF STREAM - Nature's Pharmacy and Eyes In The Sea MISSION DISPATCH 10 • 08/28/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Brian Cousin - HARBOR BRANCH Oceanographic Institution I had the unique opportunity of diving in the Johnson-Sea-Link II's aft compartment on this morning's dive [dive #3331]. John Reed was up front in the sphere with pilot Craig Caddigan, to collect samples for evaluation by the Biomedical Marine Research group, and to deploy all six of Dr. Tammy Frank's benthic traps. I ducked down and under the belly of the sub 
and climbed up through the hatchway, pushing my video camera ahead of me. Chamber tender Alan Fuller followed me in and
pulled up the hatch securing us inside. I looked out the small porthole and considered my limited field of view, and how
best to aim my camera for a steady shot.
Caddigan's voice comes over the intercom. "Okay Al, here we go. Let me know when you get a seal." He is referring to the hatch through which we entered the chamber. There is zero-tolerance for leaks aboard the sub, and should any water enter, the sub would immediately be pulled up for repair, starting with replacing the rubber o-ring seal. The massive A-frame on the back of the ship booms us out and lowers us into the waves. "We have a seal," Fuller informs the pilot. Pilot Caddigan is heard next, acknowledging the chamber tender, and relaying the information to the Submersible Operations Coordinator, or SOC, who is responsible for all aspects of the dive. Today, it's Don Liberatore. "Roger, we have a seal." Liberatore radios back, directing the sub pilot to "blow it," and the 85-pound titanium drop lock that secures the sub to the A-frame is detached by a blast of compressed air. As the sub falls back from the research vessel, the SOC radios another instruction to the pilot. "Release it," and the pilot throws another switch that disconnects the tow line from it's receptacle on the sub's upper crash bar. "Okay Craig, your lines are clear. You have permission to dive." 
With that, as the pilot replies, we're diving.
The trip to 1,700 feet below the surface takes a little under 20 minutes. The descent is remarkably peaceful. After one-and-a-half weeks, 24 hours a day on a rocking research vessel at sea, there is respite in the stillness below the waves. The ocean cradles the submersible in soothing shades of blue, gently lowering it into the dim regions where sunlight finally can no longer reach. At 900 feet I am looking into a fathomless blue-black expanse and thinking of the tiny creatures out there adjusting their bioluminescence to match the down-welling light. Do they stay at one depth? Do they have to adjust for every foot, ten feet or hundred feet that they move up or down? What if a cloud crosses the sun? At 1,400 feet, the light is all gone and I'm watching occasional greenish flashes of light as the sub disturbs the bioluminescent inhabitants of the water column. The only sounds are of the submersible's electric thrusters directing us down, and the periodic buzz of communications through water between ship and sub. Suddenly the pilot snaps on the sub's lights, their beams pierce the darkness. Through the port side view port, the bottom appears out of the gloom. It looks like a dark, coarse, sandy bottom punctuated by patches of sponges, gorgonians, and Lophelia corals. Looking a little longer, small fish and long arm crabs come into view, unmoving on the ocean floor. Immediately, Reed and Caddigan go to work in the sphere. Time on the bottom is limited and precious. Reed directs the pilot to steer the sub to something that's caught his eye. I listen in on the headset. Okay, this is sample number one. It's a Hexactinellidae, double, about 12 inches high. White." 
An image matching Reed's description is displayed on the video monitor in the aft compartment. Close-up, wide-shot and
collection. The sub moves a short distance to another sponge. "Sample number two is a yellow, fan shape sponge, 8 inches
high..." Suddenly a small shark darts into the cameras view behind the sponge. It's small, about 24 inches long. We
collect seven samples of sponges and gorgonians, and three sediment samples.
The baited traps in the JSL's collection basket prove irresistible to a large geryon crab that clambers up the side of the basket, attracted by the bait's chemistry entering the water. Made with care the day before by Dr. Frank and Nicole McMullen, the bait balls consist of fishmeal and fish parts rolled into spheres and slipped into orange mesh bags before being secured in the traps. The traps are deployed over a small area, all of them in sight of the sub. Half a dozen little sharks like the one we saw earlier, appear and cruise around the traps. Hopefully Dr. Frank will be rewarded with a good catch when the traps are retrieved on the afternoon dive. Three hours on the bottom pass more quickly than I hope, and pilot Caddigan requests permission to leave the bottom. As we ascend, we witness in reverse, the display of light and color we saw on the way down. We hit the surface and the R/V Seward Johnson maneuvers to take us down the port side. The swimmer dives in and connects the towline to the crash bar and the sub is reeled in to the back of the ship. The drop lock is lowered to the swimmer who muscles it into the receptacle on the back of the sub, and the A-frame operator booms us in. The samples are unloaded and processing in the ship's wet lab begins. The dive was great - I am walking on air. Thanks to Dr. Shirley Pomponi, John Reed and the crew for a ride in one of the world's premiere undersea vehicles. According to Dr. Shirley Pomponi, "Many of the deep water sponges and corals we're finding are new - I'd conservatively estimate that we're finding one new species of marine invertebrate each day on this expedition!" You can read more about this amazing expedition and the discoveries they're making every day on NOAA's Ocean Explorer website: http://oceanexplorer.noaa.gov 
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