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MISSION DISPATCH 2 October 03, 2005 | Claire Nouvian - @SEA Correspondent 1 pm: The R/V Seward Johnson departs from Gloucester and heads east toward Wilkinson Basin for the first dive. My good luck, Marsh has designated me to ride in the aft chamber of the JOHNSON SEA-LINK I (JSL) submersible. Incredible, I am actually going to enter King Neptune's realm! 
I squeeze my way through the hatch with the help of Tim, the sub technician who is diving with me in case of a problem. He invites me to take my shoes off if my feet don't stink. Nice to meet you too, my name's Claire. In seconds, we become physically very close, all cramped up in a long, narrow living space plumbed with gauges and connectors. Slightly aft of the hatch are two, flat window ports, one on each side of the chamber. Tim has a paperback novel with him. I can't imagine why, too improbable that he has dove so many times that he does not look out the portholes? When I ask him, he answers "there is not much to observe, you'll see". His answer is my first contact with reality in the deep sea. I should know, I've read this before. Although, the oceans teem with life, the ecosystems are so vast that the chances to encounter the wide range of natural diversity of animals in a single dive are small, and also because many animals can sense the bulky, bright and noisy submersible. Those fauna that can avoid it probably do. 
The sub is lifted from the stern by a large A-frame and splashes down into the surface of the sea. The ride inside is very smooth; I hardly noticed the movement. And here we are, going down. Depth is announced in feet and I keep converting the numbers into meters. I think of William Beebe, of Auguste and Jacques Piccard, and all the other people who like me now have had the immense privilege to observe the deep sea first hand. The first animals in view appear to be small shrimp. Marsh corrects me on the intercom. I am watching copepods, not shrimps. Of course, when I look closely, spiny antennae flair outward from each side of the head. That feature is so characteristic, how could I not recognize them? There are hundreds of these tiny (3-5 mm long) creatures swarming around the lights of the submersible. It's easy to believe that they comprise the most abundant component of the animal plankton (zooplankton). When we reach 30 m depth, the water temperature quickly falls by 10 C degrees. This region of rapid change is called the thermocline and constitutes a watery boundary. Marsh had explained earlier that the ocean is similar to a "parfait au chocolat" (you know you're talking to a gourmet). There are distinct layers of different salinity and temperature in the oceans and animals are distributed vertically in relation to these invisible frontiers. Actually not that invisible to an experienced eye. Marsh points out that the animal life is more numerous here and the visible particles that form the marine snow are notably denser. 
Inside the sub, it's becoming seriously cold. A scrubber, which absorbs the carbon dioxide we produce, constantly blows cold air on our necks. Tim and I are wearing several layers of clothing. David loaned me his fleece hat just before I began this dive. The hat is very precious now, especially when you know that 80% of body heat is lost through the head. Marsh collects a few ctenophores called Euplokamis, Bolinopsis, and Beroe. As we touch the seafloor, I see a school of large fishes, maybe cod. We are at 900 feet. On the ascent to the surface, pilot Phil Santos shuts off the lights of the sub. I have anticipated this moment for a long time, the direct observation of bioluminescence. No disappointment, the show's on. The sub is moving upward at a rate of 30 meters per minute and creates the impression of looking at a dark sky filled with shooting stars. The words of William Beebe come back to me: of their living counterparts that swim in the deep sea. " Once back on deck at around midnight, Brian Ortman, the molecular biology PhD student from the University of Connecticut, prepares some of the ctenophores and other gelatinous fauna to extract their DNA. He has been working on this project for 2 years. The idea is to identify the DNA code for each species, then to look at population genetics and try to understand whether populations from different regions interbreed. 
Marsh's main project during this cruise will focus on the predatory impact of a single species of siphonophore called Nanomia cara. Siphonophores are related to jellies but their organization is very different. They are rather the equivalent of colonies of jellies tied together along a common cord. Each animal within the colony has a specialized task, such as locomotion, food capture, digestion or defense. There are at least 150 different species of siphonophores. The order contains the largest invertebrate animal on Earth (siphonophore Apolemia uvaria, which can reach 40 meters in length) as well as tiny (3-6 cm long) siphonophores that are also important predators. Siphonophores can have up to 800 stomachs! Do they have to feed every stomach? How often do they eat? What animals do they consume? But on this dive, no siphonophores were seen, therefore no gut content analyses. As a result, Marsh decides to travel to the east to dive in George's Basin. He is hopeful that will improve our chances to find siphonophores. While everyone sleeps, captain Ralph Van Hoek guides the ship to the new location. 
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