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JULY
15:
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Deploying the trawl in fairly rough seas. Someone forgot their boots!
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A bioluminescent atolla jelly brought back from the depths.
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Low clouds touch the water over the Gulf of Maine.
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Click below to learn a bit more about this advanced and versatile deep-sea research tool...
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Tammy Frank leads an expedition that will explore a wide range of interesting marine science questions. Click below to read what it took for Dr. Frank to become a successful marine scientist...
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Accomplished videographer Brian Cousin is doing double duty on the Gulf of Maine cruise. He's gathering footage for a video about bioluminescence, and he's bringing the Gulf of Maine to your desktop as our @Sea correspondent. Click below to learn more about Brian...
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Is there a question you'd like to ask our intrepid correspondent? Send us an email at
AskAtSea@hboi.edu.
Selected questions will be forwarded to Brian, and we'll post the answers online.
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DISPATCH 8: "Have Net, Will Travel"
@Sea correspondent/photographer, Brian Cousin
JOHNSON-SEA-LINK pilot Phil Santos inside the sphere after launch. The JSL offer unparalleled underwater viewing through the 5 and 1/4" thick acrylic bubble.
July 15 --
Harbor Branch's JOHNSON-SEA-LINK I submersible made two dives today, transporting Dr. Tammy Frank and Dr. Edie Widder nearly 2,800 feet down in the Gulf of Maine. After completing light-measuring vertical profiles and beginning animal-counting horizontal transects, both dives had to be terminated due to deteriorating sea states at the surface.
Out here, conditions change extremely fast. In the two hours following both launches, fair seas became confused and then rough - again piling up waves that break over the stern and onto the main deck of the R/V EDWIN LINK.
Recovering the sub in these seas demands the full concentration of the crew. The EDWIN LINK's captain must keep the surfaced submersible off the starboard beam - not too close - the seas could pitch the bobbing sub into the side of the 168-foot vessel, but not too far away either. A swimmer has to plunge into the water pulling a heavy tow line to attach to the sub, and the shorter the swim the better. The sub Operations Director (O.D.) and the Chief Engineer operating the massive submersible handling system have to perfectly time the recovery sequence to bring the sub aboard without striking the ship or the A-frame structure. The captain helps by keeping the ship moving slowly forward, applying tesion to the tow line.
On the sub O.D.'s instruction, the Chief Engineer lowers an 85-pound titanium drop lock to the swimmer, who is perched on the back of sub. Standing on the floating sub and guiding the lock into the receptacle on the back of the sub isn't so hard when the seas are flat, but in these seas, merely standing is a challenge. The swimmer stays low on his knees as long as possible before receiving the drop lock. The waves are lifting the sub higher than the deck of the ship. A wave pushes the sub up and the drop lock misses the receptacle. The engineer quickly reels the lock back up and they try again; this time the swimmer finds the mark and it locks securely into place. For a few seconds after it clears the water, the sub and its occupants twist and swing on the line. The ship and the sub are like two out of sync dancers on a wildly shifting floor until the sub locks into the A-frame and is boomed in and lowered to the deck.
Tammy and Edie are having a challenging time gathering sufficient data for their purposes. They have pretty much "characterized" the water column with measurements of irradiance and spectral distribution. But they are unable to complete their series of horizontal transects before having to return to the surface. It's frustrating, because at the depths they are working, there is a stillness in the water that gives no hint of what's happening above.
The data they acquire during the daytime dive is still good because the light isolume, or light level is fairly stationary. But at night, when the animals and the isolume are moving, Tammy and Edie need to squeeze every minute out of their dive to accomplish the series of transects they need to observe the vertical migration. Tomorrow, the students will start taking turns riding in the aft compartent of the sub, while Tammy and Edie continue to run transects from the sphere. Most of them have never been in the JOHNSON-SEA-LINK - and are in for the experience of a lifetime. Think of the coolest thing you can do and then multiply by 100. You bet there are some excited students out here.
Among the collection of scientists and colleagues aboard is Will Jaeckle from the Illinois Wesleyan University. He's got a strong interest in the developmental stages of invertebrate larvae and how these minute creatures make their living in the open ocean. Armed with a small plankton tow and a microscope, Will has the keys to look into one of the most wonderfully peculiar worlds the ocean has to offer. "I've been fascinated by oceanic larvae ever since I was a post-doc at Harbor Branch", says Will. "There're so many different varieties of animals to look at and so little is known about them. I'm really interested in asexual reproduction, or self-cloning, in these animals - particularly starfish. The hypothesis is that cloning allows for the trans-Atlantic dispersal of starfish species. I came on this cruise to see if the animals we have found in the waters off Florida can live in these waters, and they are. That's an important find for us. They're here, they're cloning and they seem pretty happy".
I look under the microscope at a sampling of some of the most unusual looking animals I have seen. They are enigmas - studies in contrasts. Complex, yet beautifully simple at the same - fragile little alien creatures that travel thousands of miles in the vastness of the open ocean. The idea is that these microscopic plankton move with the currents from Africa to America, from America to Europe, cloning or reproducing themselves as they go. The individual that arrives at the end of the journey is genetically the same as the one that started it, but it's not the same individual. So where does the trip end, anyway?
"We don't know", says Will. "Some species settle and grow into adults. Maybe some of them never get out of the plankton layer and just drift with the current reproducing as they go".
It's no small task compiling data about these little known oceanic drifters. There is a graduate student at New Yorks's SUNY Stoney Brook campus compiling a library of gene sequences where scientists will be able to compare larval genes to known genes in an effort to determine species. Many of the adults don't look like the larvae at all, and have been described as different species.
Will says, "I've always liked larvae - asexual reproduction is just one aspect. Morphologically you've got cells that can be differentiated to become muscular tissue, part of the digestive system or something, and then somehow the cells can be switched. A skin cell can become a digestive system cell and vice-versa.
Will shows me a brittle star larvae under the microscope. "Look for the pair of small opaque arms at the end of the animal. Before the cruise is over that pair of arms will develop a whole new larvae. These animals have an incredible variety of ways to overcome the challenges of living in the open ocean. They're much better at solving problems than people. Of course we only see the successes."
Will spent 6 weeks in Barbados studying these little nomads of the sea, and gets other samples from Tammy at Harbor Branch and from the Smithsonian Marine Station, also in Fort Pierce. "I haven't been on a ship like the EDWIN LINK for three years. It's an unusual experience to collect animals out here." Will hopes his research will take him to the Cape Verde islands of Africa to see what's in the plankton there. "Have net, will travel!"
Will Jaeckle deploys a plankton trawl to capture specimens for study under the microscope.
Recovering the sub at night in rough seas is an adventure in itself. The sub's lights can be seen in the waves behind the ship.
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