Vents in the deep sea home to unique species

UK scientists exploring the ocean floor in the Caribbean have discovered an “astounding” set of hydrothermal vents, the deepest anywhere in the world. Deploying a remotely-operated vehicle, or ROV, in the Cayman Trough, they stumbled across a previously unknown site nearly 5,000 meters below the surface.

Video pictures relayed live back to the research ship mounting the operation show spindly chimneys up to 10 meters high. In the immense pressure of the sea three miles down, the ROV, known as ISIS, was gently steered around the vents, taking pictures and gathering samples.

One of the people “piloting” the ROV said seabed smokestacks remind him of “the industrial Midlands.” Hydrothermal vents are among the strangest features of the deep ocean and their existence was not known until the 1970s. Since then they have been discovered at about 200 sites around the world including the Southern Ocean and the Atlantic.

But it was only three years ago that vents were first detected in the Cayman Trough, a deep trench formed by the boundary between two tectonic plates. One set of vents, known as Beebe, was established as the deepest on record — until the discovery last night of another slightly deeper set nearby, at 4,968 meters, or about three miles. The water being blasted from the newly found vents was measured at 401 C, making this set among the hottest on the planet.

Eerie landscape

The expedition, funded by the Natural Environment Research Council, is being run from a British research ship, the James Cook, named after the 18th-century explorer who blazed a trail of discovery around the Pacific Ocean. A live stream of video is relayed back to a control room on board, where a cheer went up when the ROV’s lights and high definition cameras picked out the new vents amid total darkness. The team had been looking for a set first identified a year ago but their search took them unexpectedly into a new field.

The tallest of vents reaches about 10 meters. The chief scientist, Jon Copley of the National Oceanography Centre, said the discovery of “astounding mineral spires” was a “complete surprise.” For the biologists on board, the vents act as a highly unusual habitat with a massive contrast between the water from the vents measuring just over 400 C, compared to the surrounding sea temperature of around 4C. The narrow interface between the two extremes of water — sometimes as narrow as a few centimeter s— provides a unique environment for an array of creatures.

Ghostly-white shrimp, clustered on the rocks in teeming crowds, appear to have lost the ability to see because their eyes are fused together. Verity Nye is one of the researchers studying the blind shrimp.

“We don’t think they have functioning eyes but they have a really unusual organ on their backs which is like a warning system for them to tell them when they’re getting too hot so they don’t get too close to the hot water from the vents.

Further dives are scheduled with Japanese and American researchers planning investigations here later in the year. The scientists on the James Cook hope the research will eventually answer two key questions: why and how life evolved in such a seemingly hostile environment.