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THE MAINE EVENT: FALL 2002 Predation by Gelatinous Zooplankton in the Gulf of Maine MISSION DISPATCH 9 • 09/22/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Harry Breidahl - Marine Education Society of Australasia [MESA] 
As the third and final week of the Fall 2002 Maine Event draws to a close, it's a 'four canyons in
three days' tour - Friday 20th at Lydonia Canyon, Saturday 21st back to Oceanographer and
Hydrographer Canyons then, today Sunday 22nd, we are working at Atlantis Canyon.
The weather has been simply stunning. We have had days of balmy blue skies, light breezes and tranquil seas with just a hint of a mild swell lazily rolling through. Perfect conditions for deep-sea research and the program aboard the RV Seward Johnson II has been running at top pace. To use an Australian expression - "we've been flat out like a lizard drinking." Two dives per day aboard the submersible Johnson-Sea-Link I (JSL) are the foundation upon which each daily science program is built. The first JSL dive generally hits the water at 1.00 pm (1300 shipboard time) and is back on deck by 4.30 pm (1630 on the ship's clock). This schedule gives the sub crew and the scientists just enough time to process the collectings and then prepare the sub and all the sampling paraphernalia for the second venture into the deep. The night dive starts at 8.30 pm (2030) and lasts until midnight (back to 0000). 
Because time on a research cruise is so precious, midnight does not spell the end of proceedings.
In fact it is hard to tell where one day ends and another begins. As JSL lands on deck around
midnight, its cargo of
Nanomia cara and other deep-sea specimens head for scientists in the three
shipboard laboratories. Running parallel to this late night (or should that be early morning)
work, the 1 am (0100) to dawn shift has generally been the time for the French video profiler
(UVP) to probe the canyons of the Gulf of Maine. This activity has meant that Marc Picheral and
Tom Sornes have seen their fair share of sunrises over the past three weeks. Shortly thereafter
(0600-1000 ship's time - work it out for yourself) the
MOCNESS multi-net system is lowered to 1,000 meters. Following lunch the cycle begins again
with the next JSL trip down to a canyon floor.
One of the highlights of the last few days came on Friday afternoon. The return of all JSL dives is greeted with great enthusiasm but it is hard to top the excitement generated by the return of dive 4491. As the sub hit the aft deck we could see that the top critter gitter tube and a number of the top sample buckets were jam-packed full with a 12-foot (4-meter) long siphonophore. During the dive Marsh Youngbluth and sub pilot Phil Santos had ringside seats in the front sphere of JSL as the sub encountered this huge siphonophore at 3,000 feet (1,000 meters) in Lydonia Canyon. After obtaining 
video footage of this gelatinous giant as it extended its feeding tentacles, Phil deftly drew the
entire animal into the top critter gitter. As the animal was too big for a single sample bucket,
it ended up in a number of buckets and occupying most of the long critter gitter suction tube.
As with many of the animals encountered on this research cruise, this siphonophore (belonging to the genus Halistemma) has rarely been seen alive in its natural deep-sea setting. An entire colony has never been collected. Needless to say, when the still living specimen reached the surface, waiting scientists sported smiles that would put a Cheshire cat to shame. Sadly, today spells the end of the second year of this three year project supported by the National Science Foundation and the Harbor Branch Oceanographic Institution. The RV Seward Johnson II will head for Woods Hole around 10.30 pm (2230) tonight. On board are hundreds of specimens, thousands of photographs and gigabytes of data that will be heading back to laboratories in Florida, Spain, Austria, France and Norway. A great many fond memories and rich experiences will also be carried to far flung destinations, not least among them Australia.  |  |
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