Submarine Ring of Fire 2006

Life in the sea has often been called the least known system. We know more some say about space than the deepest oceans. Now what of the species living around vents, and the ecosystem interactions?

By Thomas Winterhoff
Esquimalt News
Jan 03 2007


New species of fish thrives in toxic environment of underwater volcanoes

It’s sometimes been said that human beings know more about the farthest reaches of the solar system than they do about the deepest regions of Earth’s own ocean environments.

However, a team of Canadian and American scientists (including a group of University of Victoria staff and grad students) made a fascinating discovery this spring that’s shed a little more light on the mysterious world beneath the waves. In some respects, their work has raised as many questions as it’s answered.

The Submarine Ring of Fire 2006 expedition was launched in May and concentrated on identifying various forms of life around active underwater volcanoes in the Pacific Ocean. The ongoing project is jointly funded by research agencies in Canada and the United States, with American organizations such as the National Oceanic and Atmospheric Administration (NOAA) providing most of the financial backing. Dr. John Dower and Dr. Verena Tunnicliffe led a UVic contingent that was also involved in a similar 2004 expedition.

“They had invited us to come along to explore a big chain of underwater volcanoes that no one had really explored before we started there in 2004,” explains Dower, who is involved in both the biology and the earth and ocean science departments at UVic.

The most recent study was focused on a series of underwater volcanoes that lie along the Mariana Arc, located northeast of the Philippines. The depth of the volcanoes varies greatly, with some just 100 metres below the surface and others located over 1.5 kilometres beneath the waves. Some of the “seamounts” in the chain have been forcing their way upward over the millennia to the point where some of them formed small islands. That process produced the island of Guam at the south end of the Arc, which is home to a major U.S. military base and served as the expedition’s starting point.

The volcanoes may lie underwater, but some of them are extremely active and constantly spew out hot plumes of sulphur and toxic heavy metals.

The volcanic activity in these “hydrothermal” areas can heat up the surrounding seawater to temperatures approaching 180 C.

Under normal circumstances, most forms of marine life tend to avoid such inhospitable environments.

The team used a remote-control submersible vehicle equipped with a video camera to scan the seabed around each volcano. It was during those surveys that the researchers captured images that were totally unexpected; a species of previously unknown flatfish (also known as a tonguefish) was swimming nonchalantly through the clouds of poisonous chemicals and was even seen resting on top of pools of molten sulphur.

“In other hydrothermal systems like this, one of the groups (of animals) that’s often curiously absent – or in very low numbers – are fish,” says Dower. “It was surprising to find these fish there... What was even more surprising was their abundance.”

See http://www.esquimaltnews.com/portals-code/list.cgi?paper=10&cat=23&id=804759&more== for the entire article.

Craig Heinselman
Peterborough, NH