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MISSION DISPATCH 4 August 20, 2007 Mark Schrope - @SEA Correspondent aboard the R/V SEWARD JOHNSON Location: Off Gouldings Cay 
No Vicious Attacks on Humans, Sponges Fare Less Well
"There was no tremendous excitement," says Justin Marshall of today's first submersible dive, "I wasn't viciously attacked by a swordfish." It actually wasn't an overdramatic statement, because on the first Deep Scope expedition that's exactly what he experienced. We saw it later on video as the huge fish came straight at the sub, then went off the screen only to smash in so hard that the camera shook. Today, Justin instead had to content himself with the more sedentary wonders of the deep. He returned with spectacular footage of a garden of crinoids, or feather stars, squirrel fish, three species of sharks, and a shrimp that had taken up residence in a rather picturesque sponge. Besides having a look around, Justin says, "Most of my dive stuff is going to be attempting the impossible." That's because his scientific goals include collecting squids or other cephalopods, and fish, all of which can prove extremely challenging to accomplish from the submersible because they move quickly. If such samples can be collected on a dive, he'll study the cephalopod eyes as part of a project to compare the vision of various species, and the fish to learn more about whether those found in the deep sea are able to sense movement better than their shallow-water counterparts. Such sensitivity could be a means of compensating for reduced light in the deep. 
Differences Like Night and Day
On the first dive, Harbor Branch sub pilot Don Liberatore also retrieved and safely returned the Eye-in-the-Sea to the joy of Edie Widder and Erika Raymond, who were waiting anxiously on deck. Having now reviewed most of the video captured by the system, the two are extremely pleased with the results. "I'm ecstatic," says Edie, " It's working, it's in focus, we've got data." So far they've seen countless sharks and fish, including a pair of very large sixgills, and clues to the animals natural behaviors are emerging from the grainy black-and-white footage. Hordes of the small, two-inch isopods—the ones akin to rolly pollys on land—have been attracted to and in many cases trapped inside the bait box. But some have also clearly been attracted to the light lure that periodically mimics bioluminescent displays, suggesting that bioluminescence may be one way they identify food. A broader revelation is that there seems to be a clear diel, or daily cycle to the animal activity, as is found in the upper reaches of the ocean. During the day there are far more smaller animals active, while during the night hours the large predators like sixgill sharks dominate. When Crabs Attack For the second dive, Misha Matz was in the sphere with Don, searching for fluorescent organisms. Misha uses special filters on the lights and camera to detect the phenomenon, which has been seen in everything from crabs to one shark species. On this dive he was able to find only fluorescent animals that he and others have already studied, along with dinner plates and a Stella Artois beer bottle. Sadly, the garbage isn't the least bit surprising as some kind of refuse is spotted on almost every deep dive anywhere in the world. Misha and Don also came upon the strange sight of another sponge attack, this time with crabs as the aggressors. Actually, there's no reason to think the sponge was being harmed, but there was an unusual concentration of crabs on and in the sponge with no obvious explanation. The hairs and joints on crabs are brightly fluorescent, so on video, captured with Misha's filters in place, the scene was especially surreal. 
Tomorrow EITS will be redeployed at a site close to the first but about 200 feet shallower. One goal will be to see if there are identifiable differences between the two depths in the animals and behaviors recorded. The weather for now seems to be holding, and in fact the forecast calls for the seas and winds to calm, so we should be in good shape for a few days. ADDITIONAL DISPATCH IMAGES [ IMAGE 01 ] [ IMAGE 02 ] [ IMAGE 03 ] [ IMAGE 04 ] [ IMAGE 05 ] [ IMAGE 06 ] 
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