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FATHOMING THE GULF STREAM - Nature's Pharmacy and Eyes In The Sea MISSION DISPATCH 3 • 08/21/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Brian Cousin - HARBOR BRANCH Oceanographic Institution The mission for this morning's sub dive [JSL II dive# 3316 - depth 2157ft.] was to recover Edie Widder's Eye-in-the-Sea camera and Tammy Frank's benthic traps, placed on the bottom the previous day almost 2,100' down. As the Johnson-Sea-Link II makes it's descent, the current begins to carry it downstream, away from the targets. From the sub tracking station on the bridge of the R/V Seward Johnson, sub tech Alan Fuller advises pilot Don Liberatore to make way on a heading that will direct it back to the targets. "Roger, 255 degrees," comes back the voice over the comm-track radio in the echoing, disembodied parlance of wireless acoustic communication through water. 
The challenge of diving the sub in or near the Gulf Stream, lies in the
fact that current speeds change dynamically through the depths all the way to the bottom. A strong 2-knot current at the surface
may be half thatjust below the surface. Or it may be stronger. Calculations must be made to determine where the sub should be placed in the water so that when it reaches the bottom, it is near its destination. A current of one-knot at the bottom would prevent the sub from making any upstream headway at all. Researchers actively study the currents. The R/V Seward Johnson has on board Acoustic Doppler Current Profilers to sample current speed and direction at varying depths. The data are displayed in rows, called Bins, over numerous columns. LaVern Taylor, with the Rosenstiel School of Marine and Atmospheric Science in Miami, Florida maintains the systems at sea. "There's a lot of heavy post-processing of the data after a cruise, but in the first three columns you can see depth, current speed East in meters per second, and then North. One display shows increments of 16 meters, the other six. Liberatore's voice breaks the ambient hum on the bridge: "We've got the first two traps in sight." The doors on the traps are closed, but Dr. Frank, seated in the sphere next to Liberatore, knows that's no confirmation the traps contain anything inside. The doors were kept open  with a small magnesium catch rigged to deteriorate in sea water over a period of
about 10 hours. Eventually, when the catch can no longer support the weight of the door, the trap is sprung. The two remaining
traps lie about 130' distant, next to Edie's highly specialized Eye-In-the-Sea camera.
The camera records continuously, but stores only 15 seconds every 10 minutes, to digital media. Additionally, it is programmed to store data whenever it is triggered by the bioluminescent flash of a passing animal, and continues to store an additional duration recorded under red light, in hopes of catching a glimpse of the animal responsible for the display of living light. The crew aboard the sub, decides to collect some other samples including sponges and gorgonians for the Biomedical Marine Research team, leaving recovery of the camera and its substantial tripod until the end of the dive. As they make their way along the bottom, weather begins to develop at the surface. A squall approaches, with lightning and rain, and winds that begin to whip up the waves. Suddenly, the prospect of returning the Eye-In-the-Sea to the ship becomes potentially dangerous, and Liberatore is advised to abort recovery of the camera on this dive. After picking up the last two benthic traps, the sub returns to the surface. As the Biomedical Marine Research team pores over the samples brought up in the collection buckets, Tammy Frank opens her benthic traps in the lightproof environmental room on the ship. From the four traps eight hagfish, each about a foot long, spill into a plastic container. "Ugh. Hagfish," Frank recalls 
from previous missions, this species and
the unpleasant slime they produce. "How disgusting."
The traps also contained a number of tiny amphipods, too small to
study for visual response and optic architecture.
Widder makes the best of her situation by making high resolution digital photographs of some of the organisms brought up in the sub's sample buckets. She checks a unique sponge with fluorescent properties for bioluminescent activity, using an intensified camera. It is difficult to stop thinking about her Eye-In-the-Sea, abandoned for now, over 2,000 feet down. It'll be recovered on a subsequent dive, of course. She is counting on good weather and fair seas. So what did the Eye see until it stopped recording about 24 hours after being launched? We'll have to wait to find out. 
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