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THE MAINE EVENT: FALL 2004 Predation by Gelatinous Zooplankton in the Gulf of Maine MISSION DISPATCH 4 • Friday, September 17, 2004 Location: Wilkinson Basin Dispatch by David Shale - photographer/cameraman, Dorset UK I will begin where Jessica left off with the night dive of the 16th September. It was my turn to dive in the sphere of the JSL submersible! Our aim at the moment was to collect specimens of the physonect siphonophore Nanomia. These specimens will be used to quantify prey consumption in situ. We'll also collect these and othermidwater fauna for measurements of oxygen consumption in shipboard laboratories. 
Sinking into the darkness, we saw very few animals, a real contrast to the
previous dive in the afternoon. Particles of detritus, called marine snow, were obvious in the
sub's floodlight, but little else was apparent as we drifted ever deeper. We reached bottom at
almost 3,000 feet and had seen relatively few animals. Consequently, the initial euphoria at the
start of the dive ebbed somewhat.
With the canyon wall in front of us and the sea floor below, we headed up. Shortly thereafter, our fortunes changed, we saw a cirrate octopus curled up ahead of us in the sub's lights, the webbed mantle wrapped around its body like a blanket. This drifter appeared to be sleeping but awoke suddenly and swam 
quickly into the darkness around us when we attempted to collect it.
Moving up to 1,900-2,100 ft, where Nanomia has been common on this cruise, we became embroiled in the process of sampling zooplankton and our dive time ticked away. After filling most of the 30-odd samplers, all the dive lights were switched off. As we floated toward the surface I was treated to a show of bioluminescent fireworks that beat any 4th of July event! As the sub touched down on the ship, the deck was awash with scientists and crew behaving like ants round a honey pot. But within a few minutes, all was quiet as the collected animals were carried to the cold and dark quarters of the ship. 
Francesc took the
medusae to classify, Brian froze pieces and parts of siphonophores, ctenophores and medusae for DNA
analysis, and Marsh selected the cirrate octopus for metabolic measurements!
The MOCNESS tows scheduled for night time sampling of hyperiid amphipods and other zooplankton had to be abandoned as the faulty bearing of the main tow winch could not be repaired. 
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