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MISSION DISPATCH 2 August 18, 2007 Mark Schrope - @SEA Correspondent aboard the R/V SEWARD JOHNSON First Dive No Disappointment The seas were a touch rougher this morning and the skies a bit greyer, but it was still plenty calm for the rest of the run to Gouldings Cay and the first dive of the expedition at about 1:00 p.m. When Sonke Johnson and Harbor Branch sub pilot Phil Santos reached the seafloor at about 2,800 feet, instead of the cliff they were expecting, they found only a mellow sandy slope. There were still interesting things to see like sea urchins with poisonous pouches on top, a swimming sea cucumber and the 10-foot sixgill shark—a relatively common deep-sea species—that buzzed them. But, interesting as these sights were, they weren't what the team needed. "We were thinking, 'We're not going to stay for long, this is not so great,' then all of a sudden it started getting really steep and became a vertical black cliff," says Sonke, and that's what they needed. 
Saved by a Sponge
They found the cliff a great place to observe fish, corals, and sponges and to collect samples of animals for the various studies back on board the ship. But they also needed at least a small ledge where they could safely place Tammy Frank's crustacean traps to catch shrimps and crabs for her studies of how their eyes work. Each time the sub would make it to what seemed like a ledge from below, they would discover a steep slope and more cliff. Finally, though, they found a spot with crabs on it that seemed like it could work. It was still a little steep, but there was a large sponge behind which they could wedge the traps. "We were a little concerned," says Sonke, because we thought, 'If we mess up, these things are going to roll all the way into the vast abyss and Tammy is going to be mad.'" We'll learn how they did tomorrow night when the sub returns to hopefully retrieve the traps. Of course they found a spot soon after that seemed even better for the traps—a small cave filled with shrimp with a sandy, flat beach in front—but there wasn't enough battery power for the sub to move the traps there, so that will have to wait for another deployment. Another overarching mission of the dive was to find an even larger flat space for deployment tomorrow morning of the Eye-in-the-Sea camera system. To their surprise, after following the cliff up for nearly 1,000 feet, they found a sandy ledge perhaps 100 yards long that should be flat enough. Once the camera is deployed we'll be able to see what really happens down there, not just the quick glimpses during sub dives of only the animals not scared away by the noise and bright lights. 
Belligerent Starfish Mob
They may not have been able to see everything down there, but the sub team did still find some fascinating scenes. "We saw an entire mob of starfish on this poor sponge that must have been getting eaten," says Sonke. "It was obviously the only good food source for a long way because everybody showed up for it." After the sub returned to the surface everyone gathered around the lounge table to watch the video highlights, including the sponge "massacre". But bear in mind these are starfish, so don't picture a barrage of sponge parts flying into the current. It was a subtle attack. The starfish were quite casual, looking almost like they were lounging with arms splayed out on the soft sponge, who probably held a different view of them. But, we take what shows we can get. The Jellyfish Dance By far the most mesmerizing sight, though, was the extended dance of an exquisite red jellyfish about the size of a human head called Poralia. It undulated gracefully and slowly back and forth in front of the camera. It's dark red color seemed so out of place against the bland bluish backdrop of the cliff that it almost seemed like the jellyfish had been superimposed on the scene by computer. Poralia, I'm told (though I haven't checked for myself) gets its color from a powdery bioluminescent pigment on its surface. This can rub off on attackers, who undoubtedly then regret messing with the jellyfish because their own attackers can then use the glow to find them. 
Camouflage
One of Sonke's research aims is to understand how deep-sea animals camouflage themselves. Throughout the dive he and Phil took video of each of the animals they could find. Later, Sonke will view this footage with varying colors filtered out. If, for instance, he finds that an animal is most difficult to see when all but blue is filtered, it may indicate that the animal is effectively camouflaged in a world where blue light is almost all there is. If instead an animal is highly visible under blue light, it would suggest that, as on land, the animal's relatively bright coloration is meant to be seen. It might be a sign to warn would-be predators that it is poisonous or tastes bad and they ought to stay away. There wasn't time for a second dive today, but tomorrow we should be on a regular schedule with morning and afternoon submersible dives and some scuba diving in between. 
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