Protect the `Serengetis of the Sea' before It's Too Late, Say Biologists ; Scientists Discover Areas of Biological Diversity Which Require Unprecedented Protection from Fishing to Prevent the Oceans from Dying
Steve Connor Science Editor, The Independent (London, England)
SCIENTISTS HAVE identified "rainforests" under the oceans where biological diversity is at its greatest. And these wildlife hotspots should be preserved to give the marine environment a chance of recovering from decades of over-exploitation, the researchers said.
Boris Worm of the University of Kiel, Germany, and Ransom Myers of Dalhousie University in Halifax, Canada, want the major nations of the world to demarcate thousands of square miles of the open water for unprecedented environmental protection.
In effect, they want the oceans to have their own national parks where any form of industrial or large-scale fishing is banned, regions they describe as the "Serengetis of the sea" after the famous wildlife park in East Africa.
"We have discovered for the first time in the open ocean there are hotspots of species diversity which we have meta-phorically called ocean Serengetis," Dr Worm said. "We were looking for the equivalent of the Serengeti on land, which is an area that is important for many large animals but also where they are vulnerable to exploitation," he said.
The oceans are home to a vast array of animals and plants, from the smallest plankton to the largest whales. Life in this world is, however, mostly invisible, little understood and, in many respects, as mysterious as outer space.
Not too long ago, scientists believed the oceans were so vast they were essentially immune to the destructive activities of humankind. No matter what we did to the land, we imagined that the sea would remain a pristine and bountiful resource.
A series of studies published over the past two years has shattered that naive belief. Teams of marine biologists analysed the powerful evidence showing the oceans are in fact dying. Using data gathered by the highly destructive long-line fishing industry, Dr Worm and Dr Myers located the areas of the North Atlantic, and the North and South Pacific where the long-line fishermen caught the most abundant and most diverse range of animals - ranging from the actual targets of their trade, such as tuna and marlin, to the "bycatch" animals such as turtles, dolphins and albatross.
"We concentrated on large species such as shark and tuna to find those special places, to find out whether they existed and, if so, where they were," Dr Worm said.
"It was surprising to find out that these major species - which roam the entire ocean basins - tend to aggregate relatively close to the major landmasses," he said. "It's not somewhere way out in the open ocean, it tends to be a few hundred miles from land."
They found the biodiversity hotspots tended to be in subtropical waters between 20 degrees and 30 degrees north and south of the equator.
That contrasts with the terrestrial hotspots, such as rainforests, which invariably occur in the tropics. One possible reason why subtropical waters are rich in species diversity is because they are regions where cold and warm-water animals can live side by side.
But the scientists also discovered these Serengetis of the high seas needed some other geological or geophysical features, such as intersecting currents bringing warm and cold water together, to create the necessary habitat for a hotspot to survive. …