At more than 2,150 meters deep in the ocean, the water pressure is a crushing 220 kilograms per square centimeter. Oceanographers who have tried to snag samples of life in these pitch-black, frigid and high-pressure places have had to suck in water at high speed and try to filter out organisms, often damaging them in the process. But a team led by Duke University, the University of Oregon and the Woods Hole Oceanographic Institution last week snatched up the intact larvae of 16 different animals.
The scientists used a new sampler, called SyPRID, which was carried to great depths by an autonomous underwater vehicle named Sentry. For more than eight hours engineers steered the robot in a precise and slow pattern. The maneuvering itself marked an achievement by barely disturbing the water in front of the craft—a common complication that pushes the tiny larvae out of a vehicle’s path before an instrument can pull them in. The long, cylindrical sampler processed large volumes of water every hour, yet did it slowly enough to not harm the fragile creatures, which are only a few hundred microns across. The final trick, according to an e-mail from Carl Kaiser, the vehicle program manager at Woods Hole, “is getting most of the larvae down to a relatively still area where they are further protected from the moving water.”
Scientists are eager to have intact specimens of common and rare organisms from the very deep ocean, especially in the early larval stages of life, because the samples can explain a lot about marine food webs, the changing nature of ocean ecosystems and how methane seeping up from the seafloor may be affecting the chemistry of the sea.
Two images of Sentry and SyPRID and nine images of the beautiful larvae can be seen in the accompanying slide show (see link below). Captions are based on descriptions by Laurel Hiebert, a team member at the University of Oregon. The work was supported by the National Science Foundation.
This article was updated from the original version on July 31, 2015.