Tuesday, 11 September, 2001, 02:38 GMT 03:38 UK
Coral reefs globally 'much rarer than thought'
By BBC News Online's environment correspondent Alex Kirby
Scientists who have compiled the first world atlas of coral reefs say they
cover a far smaller area of the globe than they had thought.
They estimate that more than half the reefs are under threat from human
Mark Spalding, lead author
The reefs are being damaged faster than researchers can collect data about
them and their ecosystems.
But countries which look after their reefs can expect handsome returns
The atlas is the work of the United Nations Environment Programme's World
Conservation Monitoring Centre (Unep-WCMC), based in Cambridge, UK.
Its estimate of the worldwide extent of coral reefs is 284,300 sq km, an
area the size of the UK and Ireland combined - under one tenth of one per
cent of the oceans.
The lead author of the atlas, Mark Spalding, said: "Previous estimates had
suggested over double or up to 10 times the area that our calculations
have now shown to exist.
"It is not that other reefs have disappeared, but rather that these
earlier estimates were somewhat crude extrapolations.
"Less than 10% of an estimated 1-2 million reef species have been
"The reefs are degrading faster than data can be collected. An estimated
58% are under threat from human activities, whilst we have no idea how
much has already gone.
"Coral reefs are highly sensitive to changes in water temperature - an
increase of one to two degrees in the El Nino event of 1998 destroyed 90%
of coral in the central Indian Ocean.
"Mass bleaching (a stress response of corals) was unknown before 1979. In
1998 it affected every region where there are reefs, leading to widespread
death of corals.
"Current sea temperature models suggest such events could be repeated
every year within 30 years."
Dr Klaus Toepfer, executive director of Unep, said: "Coral reefs are under
assault. They are rapidly being degraded by human activities.
"They are over-fished, bombed and poisoned. They are smothered by
sediment, and choked by algae growing on nutrient-rich sewage and
"They are damaged by irresponsible tourism and are being severely stressed
by the warming of the world's oceans.
Dr Klaus Toepfer, Unep
"Each of these pressures is bad enough in itself, but together, the
cocktail is proving lethal."
Indonesia has most reefs, followed by Australia and the Philippines.
France is fourth, and the UK twelfth, ahead of the US because of its
The Coral Reef Alliance said the atlas was important for highlighting the
abundance of life found on the reefs.
It said: "Several important drugs have already been developed from
chemicals found in coral reef organisms. The most famous of these is AZT,
a treatment for people with HIV infections, which is based on chemicals
extracted from a Caribbean reef sponge.
"Unique compounds from coral reefs have also yielded treatments for
cardiovascular diseases, ulcers, leukaemia and skin cancer."
And countries like Egypt and Australia are earning huge amounts from
tourism to well-managed reefs.
Mark Spalding told BBC News Online: "The atlas gives us the best picture
yet, far and away the most comprehensive assessment.
"There's damage almost everywhere. People are going to the most remote
reefs after the really valuable fish, like sharks and groupers.
"The scale of the 1998 bleaching caught everybody unawares. But scientists
still don't know how quickly corals can adapt.
"Perhaps they will adapt to what's happening. At the worst, we could see
horrific change becoming more frequent year by year." http://news.bbc.co.uk/hi/english/sci/tech/newsid_1535000/1535383.stm