Beneath the Surface
New discoveries in the Aleutians
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Working at depth presented challenges
Each person had a different job underwater. The first diver, usually Jewett, connected a 90-foot section of surveyor's tape to the skiff's anchor line and ran it out parallel to shore. As he or another diver videotaped the flora and fauna along the underwater line, a second pair of divers set along it three sets of quadrats, squares made out of white PVC pipe. The quadrats varied in size from about a yard square to less than a foot across.
Meanwhile, Mandy Lindeberg, an algae expert with the National Oceanic and Atmospheric Administration, walked the same area in the intertidal zone, where she collected seaweeds from tide pools and exposed beach.
Divers counted the number of organisms found in each quadrat, photographed them and collected samples. The area in the smallest quadrat, about 10 inches by 10 inches, was collected using a suction dredge. The underwater "vacuum" sucked the organisms into a collecting bag.
Collecting animals and seaweed from the seafloor offered challenges. One form of kelp is connected to the rocks with what scientists call a "holdfast." The divers carried paint scrapers to remove the stubborn attachments. Sea urchins were also hard to collect without the sharp spines piercing the divers' thick gloves.
Working topside
After up to an hour underwater and with collection bags attached to their waists, the divers returned to the Norseman, or as they put it, went "topside." Once on the vessel, they labeled their sample collections, organized photos and videos, and prepared samples for future study.
"There really wasn’t any downtime," said Chenelot. "If there was, we usually spent it talking to our fellow researchers about the interesting things we’d found and seen."
The divers and research team also had adventures above the water. After all, they were in one of the most seismically active regions in the world. Around 2 p.m. on July 13, 2007, they felt a fairly strong earthquake. According to Jewett, the tremor "traveled up the anchor line and up through the water column" and rattled the boat. Dasher immediately got on the radio to make sure the team was safe from potential tsunamis. The quake was magnitude 5.8 and only 30 miles away, but no tsunamis were generated.