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JULY
21:
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The R/V EDWIN LINK makes its way through the waters of the Gulf of Maine.
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The ship's galley. Fresh sushi is the surprise treat.
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Here you can see the well-defined scattering layer displayed on the ships fathometer. The vertical white lines indicate reference times recorded by Dr. Tammy Frank.
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Dr. Tammy Frank and Dr. Steve Haddock in the cold room where organisms brought from the depths are kept. The water at 3,000-feet is about 4 degrees Celsius.
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As the downwelling light diminishes through sunset, the population layer of animals migrates upward.
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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 13: Sunshine, Blue Skies, and
Work, Work, Work
@Sea correspondent/photographer, Brian Cousin
Ship's cook, Dave Kervin, proudly displays the catch of the day.
July 21 --
Luck is with us. Another fabulous weather day means we'll have a full day of operations with two sub dives, a blue-water dive, and a trawl. The Gulf of Maine is almost flat... I can't believe this is the same ocean we were in a week ago, where waves broke over the deck and operations were being approved or cancelled on an almost minute-by-minute basis. Threatening skies have given way to clear blue, and the ocean is a royal blue carpet spreading as far as the eye can see.
A few members of the crew partake in a little early morning fishing off the stern of the RESEARCH VESSEL EDWIN LINK (RVEL). Two nights ago we had sushi, prepared on board by the ship's cook from a ten-pound yellowfin tuna he caught earlier in the day. Last night we grilled swordfish for thirty people--a meal funded by ten steaks and a t-shirt that we traded with a fishing boat captain operating in our area.
With only one full day of operations left in the cruise, the science crew is still putting in fourteen to eighteen hours a day in the lab, in the sub, and in the water. They're collecting samples, performing experiments, acquiring images, and entering data into laptop computers. Despite the picture perfect weather, no one is relaxing on deck with an ice-cold drink.
With all of their data collection and sampling, Dr.s Tammy Frank and Edie Widder are making good progress toward understanding vertical migration. Tammy says she feels fortunate to have made as many dives in the JOHNSON-SEA-LINK submersible as they have. "We only lost two or three days to the weather. That's pretty good. When we plan a cruise we ask for two weeks knowing there's more than enough to do in that time, but what we really hope for is at least ten good days."
Since arriving here eleven days ago, the scattering layer visible on the ship's fathometer has grown stronger, and developed a very well-defined leading edge. Tammy and Edie aren't convinced this dense layer is made up entirely of animals they are working on...they suspect there may be other creatures, perhaps too small to see, filling out the layer. The strategy for the remaining dives will be to position the sub exactly on the leading edge of the layer, and then exactly in the center, following directions given from the bridge of the RVEL. At the corresponding depths, the scientists will verify the animals present. They're certain that krill are at the leading edge of the migration, but the sergestids they expect to see coming up after them haven't made an appearance. "We're not seeing them in the shallow water," says Tammy. "It's unclear what's in the center of the layer. We haven't gotten enough repetitive samples to know."
Tammy says she could easily spend more time here on this cruise, diving in the sub, collecting data for her research. She and Edie will be back in September but the conditions will have changed significantly. "In September the abundance of animals isn't as great, and there aren't the clear scattering layers like there are now. Three more weeks here now would be great, except we'd all burn out."
So the field research continues at full speed aboard the EDWIN LINK. Back in their lab at Harbor Branch Oceanographic Institution, Tammy and Edie will analyze the host of data they have accumulated here: irradiance readings, sonar information, logs of species identification and population counts collected during submersible dives, and observations from shipboard experiments. As pioneers of innerspace, they hope their data will reveal the keys to understanding one of the most remarkable yet little-known phenomenon on our planet--the massive daily vertical migration of species in the open ocean.
Out on deck with no land in sight, it sometimes feels like we're the only ones left on the planet. The Concorde passenger jet shatters that illusion twice a day as it zooms overhead on its flights between New York and London. The loud double bang that occurs as the jet breaks through the sound barrier is a jolting reminder that the rest of the world is still out there.
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