Conservation

Greenpeace Submarine Catalogs Life on Antarctica’s Seafloor

The expedition aims to build evidence in support of establishing a protected marine reserve off the coast of the Southern Continent.

TA two person submarine at the surface after a dive, next to Greenpeace ship the Arctic Sunrise at Livingston Island, Antarctica. Greenpeace is conducting submarine-based scientific research to strengthen the proposal to create the largest protected area on the planet, an Antarctic Ocean Sanctuary. | Christian Åslund/Greenpeace
TA two person submarine at the surface after a dive, next to Greenpeace ship the Arctic Sunrise at Livingston Island, Antarctica. Greenpeace is conducting submarine-based scientific research to strengthen the proposal to create the largest protected area on the planet, an Antarctic Ocean Sanctuary. | Christian Åslund/Greenpeace

Deep beneath the frigid oceans off Antarctica lies a haven for marine life adapted to one of the most hostile places on Earth.

Researchers from Greenpeace recently dove to the seafloor off the Antarctic peninsula in a small submarine and cataloged a rich variety of species in an area the environmental organization hopes to see protected.

“It really looks like a garden, although it’s all animals,” Greenpeace marine biologist John Hocevar told Seeker. “It’s too deep for light to penetrate, so there are no plants. But we’re seeing really dense assemblages of sponges, corals, sea squirts, bryozoans, and all kinds of relatives of sea stars.”

At more than 1,000 feet (305 meters) below the surface, the population is mostly invertebrates. The water temperature is too cold for most fish, Hocevar said. The surrounding ocean is about 1 degree below zero Celsius (30 degrees Fahrenheit), kept from freezing by the salt in the water.

The fish that do survive in the waters carry a protein in their blood that serves as a kind of natural antifreeze. The Greenpeace expedition spotted a few, including a species of crocodile icefish that researchers are still trying to identify, since few have been cataloged alive.

“You try to identify it at the species level from existing images, and they’re nearly all from specimens collected in trawls or on hooks,” Hocevar said. “Comparing this fish in its natural habitat to something that’s dead and desiccated is a little bit more challenging than I would have thought. Even the experts on some of these species have never seen one alive.”

The Antarctic feather star, Promachocrinus kerguelensis, found at approximately 300 meters depth at Kinnes Cove, Antarctic Sound found at approximately 300 meters depth at Kinnes Cove in the Antarctic Sound. Greenpeace is conducting submarine-based scientific research to strengthen the proposal to create the largest protected area on the planet, an Antarctic Ocean Sanctuary. | Christian Åslund/Greenpeace
Image of the Antarctic seafloor | Greenpeace

The two-person, battery-driven submarine is lowered over the side of the Greenpeace ship Arctic Sunrise. It’s about the size of a small car, and cramped: “If you turn your head, you might knock something over,” Hocevar said.

The expedition was aimed at building evidence to support the establishment of a protected marine reserve off Antarctica by an international body that oversees commercial fisheries in the high Southern latitudes. That group, the Commission for the Conservation of Antarctic Marine Living Resources, is expected to revisit the proposal in October after failing to agree on previous attempts.

Glacier front and icebergs at Joinville Island, facing the Antarctic Sound at the opening of the Weddell Sea. Greenpeace is conducting submarine-based scientific research to strengthen the proposal to create the largest protected area on the planet, an Antarctic Ocean Sanctuary. | Christian Åslund/Greenpeace

The Antarctic peninsula is warming faster than anyplace on Earth as a result of climate change, Hocevar said, while fishing for shrimp-like krill threatens a species that’s a staple food for whales, penguins, and sea birds. Humans use it mostly for fish food or dietary supplements, though a small percentage is eaten by people.

“It’s already quite large, and there is talk of a significant expansion,” he said. “So there’s real concern about that.”