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MISSION DISPATCH 2 August 21, 2005 | Brian Cousin - @SEA Correspondent At sometime during the night we arrived at our first site for undersea operations. The great clue to that fact is the relative quiet that has descended over the ship. Noise from the engines running at transit speed is absent and we can feel the gentle rocking of the ship as it moves slowly forward through the light seas. Dr. Tammy Frank is on the bridge with second mate Mike Schoeller and sub ops coordinator Craig Caddigan, scrutinizing the display on the ship's fathometer. They are looking for the telltale rise and fall that indicates we are cruising over the lithoherms on which we intend to dive in the JSL. This first manned submersible dive of the mission will take Dr. Edie Widder and pilot Tim Askew, Jr. to the sea floor to deploy Edie's Eye-in-the-Sea (EITS) camera system as well as the small sardine-baited traps Tammy is using to capture subjects for her research. They'll make light measurements using the LoLAR (Low Light Autocalibrating Radiometer). Engineer Lee Frey will ride in the back with sub tech Jimmy Nelson. 
Soon, a small mound appears on the fathometer's display at the anticipated
coordinates, at a depth of 1,860 feet. Further transecting reveals
another larger mound, perhaps 30 feet high and 40 feet across, 1200 feet
to the north-west. The team chooses the smaller mound as a target, and
preparations for the dive begin.
Traps are loaded into the collection basket for placement on the bottom. The EITS, with its newly designed camera alignment mechanism, is baited and slid over two prongs extending from the front of the sub's work platform. Erika Raymond is in charge of baiting the EITS and tries a large fish head too big for the container before settling on the tail of the fish and a few ballyhoo purchased from a Fort Pierce bait shop. The wahoo head will not go to waste though - it will be cut up and used on subsequent dives with the EITS. In fact, the wahoo was caught yesterday , and will be on the menu (minus head and tail) for lunch tomorrow. The first launch goes smoothly, with only a minor delay as the EITS new frame comes close to the ship's safety rail as it is boomed out over the stern. By raising the telelink on the massive A-frame submersible handling system, the JOHNSON-SEA-LINK I (JSL) and the Eye-in-the-Sea clear the rail with room to spare. The sub is lowered into the water, the lines are cleared and the sub pilot receives permission to dive from the sub ops coordinator on deck. Air in the ballast tanks is purged and replaced with sea water, and the vertical thrusters on the 4-man sub churn the water furiously as they push it downward. After a moment the tinny sound of underwater communication between the Seward Johnson and the JSL can be heard throughout the ship, unintelligible, except to Jim Sullivan at the Comm-Track station on the bridge. The SSB (Single Side Band) radio used to communicate with the sub looks like a relic from the 1940's. It's really 1970s technology, but it's highly reliable and still in service. After three hours, the Eye in the Sea and Tammy's traps have been deployed, and the sub heads for the surface. 
The sub returned with a galatheid crab in one of its collection buckets.
Dr. Sonke Johnsen spirited it away to his lab to determine if its
coloration, which under white light includes shades of red, orange and
brown, appears as a more broken field when viewed under a 480 nm filter
that replicates the blue color in the dark depths. As it turns out, the
coloration appears very mottled when viewed this way, providing the crab
excellent camouflage among the corals and rocks. Later, Tammy will study
the eye structure and function using her physiological prep.
Four of the five scuba divers made their first blue-water dive of the mission folllowing the return of the JOHNSON-SEA-LINK to the deck. The Seward Johnson's small boat took the dive team about 300 yards away from the ship, where we deployed a blue-water diving rig and rolled over the side into the blue abyss. The blue water rig is a system of individual diver tethers that connect to a common down line that connects to a float, that connects to the small boat. It keeps the divers together, prohibiting them from drifting off or going too deep. A solitary barracuda eyed us for awhile, as Justin Marshall made video recordings using a camera outfitted with a special lens that alternates vertical and horizontal polarization frame by frame. This illustrates how transparent creatures in the water may be significantly more visible to predators capable of seeing polarized light. Ocean currents are like highways that transport small animals along quickly, though, making specialized video recordings difficult. Sonke helps by capturing a small terapod in a thin glass case that allows Justin more time get the footage he needs. 
This afternoon, the JOHNSON-SEA-LINK returned to the bottom to check on
the status of the Eye-in-the-Sea and to collect Tammy's traps. To prevent
blinding animals that may be in the trap, the sub turned off all its
lights except two that were fitted with red and orange filters. These
lights are all but invisible to the animals, but allow the subs occupants
to see the traps well enough to pick them up and place them in the
light-tight containers for the trip to the surface. Tammy could see a
number of large cancer crabs around the traps (on top, below, in front of)
as they approached under the dim light, but they were too large to fit
into the traps. Unfortunately, they apparently considered this their new
territory, and kept smaller crabs and crustaceans away, as the traps were
empty. Undeterred, Tammy went to Plan B and collected some of the crabs
using the JSL's suction hose. The hose has been modified for this mission
with an insert to prevent samples being sucked all the way through to the
usual collection buckets. Instead, they can deposited in the light-tight
containers. The galatheids suctioned in this manner proved to be
unusually adept at hanging onto the suction screen, but one crab in
excellent condition was deposited into a Bio-Box, and arrived at the
surface alive and in fighting form, and will be used in experiments
tomorrow. As Plan B wasn't smashingly successful, on her next dive,
Tammy will go to Plan C. Stay tuned - it's early in the mission, and
modifications are already in the works.
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