Quarter of world's corals destroyed

A A A

More than a quarter of the world's coral reefs have now been destroyed, mostly in the past decade, and nearly three-quarters are likely to be gone within 50 years, a startling new international study says.

More than a quarter of the world's coral reefs have now been destroyed, mostly in the past decade, and nearly three-quarters are likely to be gone within 50 years, a startling new international study says.

The report, by the official Global Coral Reef Monitoring Network, is the most alarming yet on the fate of the richest and most beautiful celebrations of life in the seas. Although corals cover only one-fifth of 1 per cent of the area of the oceans, they are home to one-quarter of all their species.

The report documents how the reefs of 93 countries - living entities built over centuries by tiny creatures - are being destroyed by over-fishing, pollution, global warming and tourism.

The United Nations Environment Programme, one of the international bodies that established the monitoring network, has just set up a Coral Reef Unit to tackle the crisis. Professor Klaus Töpfer, its executive director, said: "Coral reefs may be the equivalent of the canaries in coal mines giving early warning that the world's ecosystems can no longer cope with growing human impact."

The report says that by 1992 10 per cent of the world's reefs had been lost, but this had shot up to 27 per cent by the end of last year. The worst-affected areas are the Indian Ocean, where 59 per cent of the reefs have been lost, the Middle East (35 per cent) and South-East and Eastern Asia (34). The healthiest ones are in the Pacific and off Australia.

The Caribbean, which has lost about a quarter of its reefs, has some of the longest-standing problems. Decades of over-fishing and pollution have severely undermined the reefs' health, making them prey to disease.

Sewage and fertiliser running off the land encourage the growth of algae which choke the living coral polyps and cut off their supplies of light and oxygen. Over-fishing makes this even worse because it takes away the fish that would otherwise eat the algae and keep them in check.

Building on the coasts - or even cutting down forests inland - causes soil to be washed into the sea, smothering the polyps. Garbage has the same effect. Chemical and oil pollution poisons them and so does cyanide often used by fishermen to stun their prey off the Philippines and other areas.

Reefs are mined and dynamited to provide construction materials and careless tourists can also damage them by dropping anchors from pleasure boats onto the reefs, or even walking on them.

The biggest threat of all, however, says the report, is global warming. When water temperatures get too high the polyps turn white and die. About 16 per cent of the world's reefs were destroyed by such "bleaching" in just nine months in 1998, when temperatures in parts of the tropics exceeded all records, particularly affecting the Indian Ocean, South-East Asia and the far-western Pacific. In many areas, 60 to 90 per cent of the reefs were lost. The Seychelles, Maldives, Philippines, Kenya and Taiwan were among the worst-affected areas, but Australia's Great Barrier Reef and most of the Pacific largely escaped.

Some of these reefs, the report says, may revive if the oceans cool again, but scientists fear that as global warming increases the crisis will go on getting worse. It predicts that if global warming and other damage continues, 40 per cent of all the world's reefs will be lost by the end of this decade, and 70 per cent by the middle of the century. The effects will damage economies: 20 countries have few sources of income other than fish caught on the reefs and the tourists the corals attract.

Have you tried new the Independent Digital Edition apps?
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

Recruitment Genius: Web Developer - Junior / Mid Weight

£15000 - £25000 per annum: Recruitment Genius: To support their continued grow...

Recruitment Genius: Marketing Data Specialist

£22000 - £25000 per annum: Recruitment Genius: They are the go-to company for ...

Recruitment Genius: Search Marketing Specialist - PPC / SEO

Negotiable: Recruitment Genius: This is an opportunity to join the UK's leadin...

Recruitment Genius: Sales Administrator

Negotiable: Recruitment Genius: This caravan dealership are currently recruiti...

Day In a Page

Greece debt crisis: What happened to democracy when it’s a case of 'Vote Yes or else'?

'The economic collapse has happened. What is at risk now is democracy...'

If it doesn’t work in Europe, how is it supposed to work in India or the Middle East, asks Robert Fisk
The science of swearing: What lies behind the use of four-letter words?

The science of swearing

What lies behind the use of four-letter words?
The Real Stories of Migrant Britain: Clive fled from Zimbabwe - now it won't have him back

The Real Stories of Migrant Britain

Clive fled from Zimbabwe - now it won’t have him back
Africa on the menu: Three foodie friends want to popularise dishes from the continent

Africa on the menu

Three foodie friends want to popularise dishes from the hot new continent
Donna Karan is stepping down after 30 years - so who will fill the DKNY creator's boots?

Who will fill Donna Karan's boots?

The designer is stepping down as Chief Designer of DKNY after 30 years. Alexander Fury looks back at the career of 'America's Chanel'
10 best statement lightbulbs

10 best statement lightbulbs

Dare to bare with some out-of-the-ordinary illumination
Wimbledon 2015: Heather Watson - 'I had Serena's poster on my wall – now I'm playing her'

Heather Watson: 'I had Serena's poster on my wall – now I'm playing her'

Briton pumped up for dream meeting with world No 1
Wimbledon 2015: Nick Bollettieri - It's time for big John Isner to produce the goods to go with his thumping serve

Nick Bollettieri's Wimbledon Files

It's time for big John Isner to produce the goods to go with his thumping serve
Dustin Brown: Who is the tennis player who knocked Rafael Nadal out of Wimbeldon 2015?

Dustin Brown

Who is the German player that knocked Nadal out of Wimbeldon 2015?
Ashes 2015: Damien Martyn - 'England are fired up again, just like in 2005...'

Damien Martyn: 'England are fired up again, just like in 2005...'

Australian veteran of that Ashes series, believes the hosts' may become unstoppable if they win the first Test
Tour de France 2015: Twins Simon and Adam Yates have a mountain to climb during Tour of duty

Twins have a mountain to climb during Tour of duty

Yates brothers will target the steepest sections in bid to win a stage in France
John Palmer: 'Goldfinger' of British crime was murdered, say police

Murder of the Brink’s-MAT mastermind

'Goldfinger' of British crime's life ended in a blaze of bullets, say police
Forget little green men - aliens will look like humans, says Cambridge University evolution expert

Forget little green men

Leading evolutionary biologist says aliens will look like humans
The Real Stories of Migrant Britain: An Algerian scientist adjusts to life working in a kebab shop

The Real Stories of Migrant Britain

An Algerian scientist struggles to adjust to her new life working in a Scottish kebab shop
Bodyworlds museum: Dr Gunther von Hagens has battled legal threats, Parkinson's disease, and the threat of bankruptcy

Dying dream of Doctor Death

Dr Gunther von Hagens has battled legal threats, Parkinson's disease, and the threat of bankruptcy