While news of space missions has dominated the headlines recently, the world's biologists and oceanographers have gone fishing, uncovering secrets of an unexplored frontier right here on Earth. An international expedition to study life in the Atlantic Ocean is back with new information, deep sea mysteries, and stories of the one that got away.
The Norwegian ship G.O. Sars returns to the city of Bergen after a two-month exploration of the depths of the mid-Atlantic. The Norway-led trip is part of the 10-year, $1 billion, international research program called Census for Marine Life.
The mission involved 60 scientists from 13 countries and took years of planning. Researcher Mike Vecchione of the Smithsonian Institution in Washington went on the expedition and explains that 95 percent of the living space on Earth is in the deep sea.
"A lot of people have said we know more about the backside of the moon than the bottom of the ocean," he said. "That's why there's a need for this work, because we really don't know what lives on our own planet."
The scientists sampled waters from Iceland to Portugal along an underwater mountain chain called the mid-Atlantic Ridge. They used nets, robot submarines, and a device called an echo-sounder to get a picture of life 4,000 meters underwater. Chief researcher Olav Godoe explains that the echo-sounder uses sound waves to find objects like fish and squid in the water.
"The echo-sounders, they send out a defined sound pulse of different frequencies. And when the sound pulse hits an object down in the water, there is an echo coming back. And the transducer records the echo coming back and analyzes it," he said.
The echo-sounder helped Mr. Godoe study how many animals are living in the deep sea and how animal communities migrate through the water. Scientists are surprised to find that one area on the mid-Atlantic ridge, called the Charlie Gibbs Fracture Zone, is an important oasis for deep sea life. They found fish and squid that may well be new species and learned more about plankton and other small particles that make up the basis of ocean life.
Mr. Godoe says the expedition raised new questions. Scientists found unexplained burrows in the sea mountains they think were made by a hidden, unknown animal. They also saw what they think is an entirely new type of creature. Mr. Godoe describes the mysterious animal as having a head and a tail, but being soft like a jellyfish. He thinks this sea creature could have its own category in the animal kingdom, which means it may be as different from any known animal as an insect is from a mammal. However, researchers were not able to capture one of the animals for further examination.
At the Smithsonian Institution, Mike Vecchione hopes there will be a return expedition to the mid-Atlantic ridge, to help solve some of the mysteries found there and to get more perspective on how the ridge may change over time.
"This was a very comprehensive program, but it's just a snapshot," he cautioned. "We don't know how much it would change from summer to winter, for instance, or how much it would change from year to year."
Mr. Vecchione says scientists also need to compare life on the ridge with other locations in the world. He says that a deep-sea mission to the Gulf of Mexico led by the U.S. National Oceanic and Atmospheric Administration began August 7, 2004. Mr. Vecchione adds that all ocean exploration is important, because we may be causing unknown changes to the deep sea.
"We don't know for instance, how global climate change will change the deep oceans, but there's some evidence starting to accumulate that it might," he said. "Also, fishing industries are working deeper and deeper in the ocean and trying to understand what lives in the deep ocean before it gets impacted by human activities is very important, so that we know when things are changing and we can explain what's happening and maybe why it's happening."
Mr. Vecchione says now that the G.O. Sars has returned to port, the real work is just beginning. Scientists from around the world will analyze the ocean data and animal species the ship brought back, fueling years of research and discovery.