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THE MAINE EVENT: FALL 2004 Predation by Gelatinous Zooplankton in the Gulf of Maine MISSION DISPATCH 9 • Wednesday, September 22, 2004 Dispatch by Sofie Backman - University of Kalmar/University of Umea, Norway Early Tuesday morning and yet another MOCNESS tow to collect planktonic crustaceans! We are using a multi-probe. micro-optode system to quantify oxygen 
consumption rates by copepods, amphipods and euphausiids (=krill). After trial and
error repairs and careful calibrations by
Calle and
Ulf
during the first few days of the cruise, the micro-optode gear is recording consistently.
You can always count on Swedish craftsmanship and ingenuity! Both Ebba and I are relying on
this one-of-a-kind instrument for our research projects.
A unique diving adventure with the Johnson-Sea-Link submersible is waiting for me this afternoon. A major objective for the dive will be to survey deep-sea fish populations living just above the seafloor in Oceanographer Canyon. We also plan to catch a variety of soft-bodied fauna that live in the benthic boundary zone, especially the long-stemmed colonies of siphonophores and the tiny appendicularians in their mucoid houses. 
We entered the sea with a splash and as we descended the color of the water outside the porthole
of the dive chamber changed from bright emerald to dark azure blue and then dimmed to black.
It was an awesome experience watching the gradual decrease in the sunlight's intensity. Before
long (about 40 minutes) we were looking at the carpet of sand on the seafloor at 3000 feet. Here,
the hunt for demersal fishes began. As expected, witch flounders, snail fishes, eel species,
several rays and small sharks appeared in the "headlights" as we transected just above the bottom.
When we encountered rocky outcrops the biological diversity of epibenthic invertebrates always
increased. In most instances, numerous sprigs of soft corals and sea anemones were observed.
On the ascent, we paused at 2400 feet and watched a small (1-inch tall), bright red cydippid ctenophore dangle a pair of long (=at least 30 inches) creamy-white, super-fragile tentacles. After awhile the pilot Hugo Marrero smoothly captured this delicate animal in perfect condition within a D-sampler. When we returned to the mother ship Per and David photographed this sparkling jellyfish, an as yet, undescribed species. Per usual on every dive, colonies of Nanomia cara were carefully inhaled with the rotary suction sampler, one siphonophore colony per canister, each one preserved immediately thereafter. The prey contained in their many (=up to 115 per colony) gastrozooids (=stomachs) will be identified and counted by Celeste, Brian, Jessica, and Marsh. Nanomia cara have fed mainly on the resting stage of a calanoid copepod (=Calanus finmarchicus) and adults of a krill (Meganyctiphanes norvegica), but occasionally other mesopelagic animals. Today one gastrozooid contained a bristlemouth fish called Cyclothone. 
After about 3 hours, it was time to return to the surface. On the way up, the pilot turned
all the lights off and we enjoyed watching explosions of blue-green bioluminescence. These
errie chemical flashes are produced by nearly every kind of planktonic animal. The displays
were one of nature's finest shows.
In the evening, petite "Sam" Christiansen, the assistant steward onboard, had her first ride in the dive chamber of the JSL submersible. This opportunity was an adventure she had wanted ever since she began working on the R/V Seward Johnson II. Her wish came true. Sam's comments afterwards were: "It was absolutely incredible! I saw a 60 foot snake-like animal with lights on its back! It was the most thrilling experience since my firstborn!" Now, I suppose, the foremost wish of the scientists onboard is to get a glimpse of this amazing creature themselves! 
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