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MISSION DISPATCH 4 October 05, 2005 | Claire Nouvian - @SEA Correspondent Franz and Andrey, our resolute ichthyologists, get up at around 5 am to deploy towed nets in the water column. The MOCNESS sampling gear aboard the R/V Seward Johnson is quite sophisticated. Eight nets can be opened and closed at any depth and time interval in an effort to learn more about where various animals live and when they migrate. Today, samples were collected every 100-m from 900 meters. 
When the nets are hauled from the water, Franz and Andrey remove the cod ends and empty the collections into sequentially-numbered buckets that correspond to the sampled depths. Many animals are damaged, most are moribund or dead, but surprisingly, some individuals survive. These living organisms are carefully separated and examined. The most hardy and unusual fauna are given to David for photography. One of the nets captured an usual pelagic animal, a finned octopus. This spineless creature has two captivating eyes situated beneath a layer of pinkish and transparent skin. The eyes lack a lens and the retina is very reduced. And so, this creature cannot form an image and perceives only dim light. Nevertheless, we can imagine it must have been a graceful swimmer when alive. The cephalopod was eventually preserved and will be sent to a specialist for identification and archival at the Smithsonian Institution. When back in their shore-based labs, Franz and Andrey will perform DNA and morphometric analyses to identify various larval and adult fish species. 
Chuck and Kelly conducted the first canyon dive at 1 pm. When they returned from 3000 feet (1000 m), the sampling canisters onboard the JOHNSON SEA-LINK I (JSL) were filled with ctenophores, medusae and siphonophores. All of these zooplankton are alive and quickly taken to the cold room. Marsh and Kelly have bundled up with layers and layers of clothes before working at 5 C for an hour or more in red light conditions to set up experiments with an unobtrusive fiber optic instrument. The most robust individuals are placed in special chambers and measurements of oxygen consumption are initiated to estimate their metabolic needs. When they finally leave the room, their hands are numb and pink. The fiber optic system in the cold room is linked to a computer in another laboratory and measurements of oxygen in the experimental chambers are monitored continuously for at least 12 hours. A more traditional chemical method (called Winkler titration) is also made to ensure that the micro-optode data are reliable. 
Because gelatinous creatures have few predators and are capable of very rapid population growth (called "blooms"), it is important to learn how much oxygen and food they can remove from a given zone. This information enables scientists to estimate to what extent gelatinous fauna compete with other animals such as fishes for food resources like copepods and krill. For the evening dive, David and pilot Don Liberatore are in the front sphere; Brandy and sub technician Jimmy Nelson occupy the aft chamber. Off they go with everyone's wish list in mind. When they return just after midnight, each bucket carries frisky treasures, there are enough animals to make everyone happy. The usual hussle of frenzied activity begins; buckets and samplers are lifted, handled, passed on, opened, talked about, looked at. 
David has a very special surprise, a finned octopus called Stauroteuthis sertensis, often nicknamed "Dumbo". This streamlined cephalopod is amazing, fantastic, awesome, and nimble. All at once! I am spellbound. It's actually very small, only about 20 cm! This feature makes him even more attractive. We put him straight into the kreisel (a round photographic aquarium) and spend several hours observing him and taking pictures. Anthropomorphism is not an objective attitude, but how could one not compare the webbed arms of that octopus with an 18th Century ballooning silk dress? How could you avoid falling for his gentle and shy expressions? His flabby ear-like fins? While lying in bed that night as the boat was bobbing with the swells, I pictured our relatively small hull floating like a cork thousands of meters above a universe filled with extraordinary creatures. There is still so much we don't know about marine life. 
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