Ten key coral reefs shelter much of sea life
American Association Scientists identify vulnerable
marine 'hot spots' with the richest biodiversity on earth
Tim Radford in Boston
Friday February 15, 2002
The Guardian
Conservationists could save a huge number of marine species
by protecting just 10 coral reef "hot spots" around the world,
scientists argue today.
A team from Britain, Canada and the US, led by Callum Roberts
of York University, reports in Science that the 10 reefs account
for 0.017% of the oceans, but are home to 34% of all species
with limited ranges.
Coral reefs are under threat, from tourism, fishing, development,
pollution and global warming. Scientists warn that most of the
world's richest reef systems could be destroyed this century. A
quarter have already been severely damaged or destroyed. Dr
Roberts and his colleagues looked at 18 areas with the greatest
concentrations of species found nowhere else, and selected the
10 most vulnerable.
They are in the Philippines, the Gulf of Guinea, the Sunda
islands in Indonesia, the southern Mascarene islands in the
Indian ocean, eastern South Africa, the northern Indian ocean,
southern Japan, Taiwan and southern China, the Cape Verde
islands, the western Caribbean, and the Red sea and gulf of
Aden.
"One of the arguments is that there is nothing we can do, it is all
going to go to hell, and that coral reefs are doomed. The other
argument is that we should work very hard to try and do
something about protecting them," Dr Roberts said. "The
question then is how? Where are we going to focus our efforts,
given that we don't have the resources to do all that we would
like? We cannot save all coral reefs everywhere."
The researchers mapped the geographic ranges of 3,235
species of reef fish, corals, snails and lobsters, which require
healthy reef environments to survive.
"One of the most effective ways to protect coral reefs is to
establish networks of marine reserves that are protected from all
fishing. By minimising the stresses of overfishing, they should
be able to cope with the stresses such as global warming," he
said.
But eight of the 10 reefs were near coasts that were being
dramatically altered by humans. The felling of forests meant that
soils were easily eroded, which deposited muds that could
choke the reefs. Farming, too, released nutrients that
encouraged seaweeds to grow where corals would once have
flourished.
"We want to avoid that, and countries like the Maldives
strenuously want to avoid that, because it means their islands
might disappear if reefs start eroding," he said.
·Humans - one species among perhaps 10m on the planet-
consume, divert or waste around 45% of all plant growth on
Earth and more than half of all renewable fresh water, Peter
Raven, president of the American Association for the
Advancement ofScience, said in Boston last night. "We have
altered substantially the characteristics of the land, the fresh
waters of the Earth and the seas, and are driving a major
proportion of the species, fundamental for our continued
existence, to extinction."
Species extinction over the past 65m years had run at about
one species per million per year. It had risen in the past 300
years to 1,000 per million species per year.
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