Coral reefs face extinction

view gallery VIEW GALLERY

A third of the world’s coral species are threatened with extinction, according to an international study that revealed rapid and alarming deterioration in the state of coral reefs over the past 10 years.

Many will have disappeared by the end of the century unless global warming, pollution and over-fishing are curbed, warned scientists in the most damning and definitive assessment on tropical corals yet delivered.

Coral reefs, the only living structures that can be seen from space, are often compared with tropical rainforests for the diversity and wealth of wildlife and plants that live in and around them. Their loss could also threaten the 25 per cent of marine species that need them for survival, as well as endangering the livelihoods of the estimated 200 million people who rely on them either for food or as a source of income.

An international team of scientists found that 231 of the 704 reef-building corals the study was able to assess were in such a poor state that they had fallen into the three most-threatened categories of species as defined by the International Union for the Conservation of Nature (IUCN). Its Red List of species has seven categories. As of yesterday, the 231 coral species on the Red List have been formally classified as either “vulnerable”, “endangered” or “critically endangered”.

The 39 scientists from 14 countries also investigated the remaining 141 reef-building coral species but could not gather enough information on them to make an accurate assessment. But they believe many of these corals are also highly likely to be threatened with extinction.

What made the study even more urgent was scientists’ ability to calculate what state the corals were in before 1998, when a significant rise in sea-surface temperatures was linked with a worldwide outbreak of coral “bleaching”, when corals as far apart as the Caribbean and the Indian Ocean lost their colour because of heat stress.

The scientists found that only 13 species of reef-building corals before 1998 would have fallen into the three most-endangered categories. This means there has been an almost 20-fold increase in the threat to corals in a decade.

They cited rising sea temperatures, caused by global warming, pollution from such human activities as sewage and agricultural run-off, and over-fishing as the biggest threats. But they warn that all of these may be eclipsed by the threat of rising ocean acidity caused by increases in atmospheric carbon dioxide, which could eventually dissolve the calcium carbonate skeletons of reef-building corals.

Kent Carpenter of the Old Dominion University in Norfolk, Virginia, who directed the global coral assessment for the IUCN, said the threat to the corals is probably unprecedented in modern times. “The results of this study are very disconcerting,” Dr Carpenter said. “When corals die off, so do the other plants and animals that depend on coral reefs for food and shelter, and this can lead to the collapse of entire ecosystems. If you are interested in biodiversity I would say this is one of the most alarming findings in terms of marine life.”

The threat of the extinction of corals could match the mass extinction that wiped out almost half of the corals 65 million years ago, along with the dinosaurs, in a geological event known as the Cretaceous-Tertiary boundary, he said. “We know that conditions existed on Earth that allowed huge numbers of extinctions. These extinctions that existed in geological times could be mimicked by what is happening on Earth today.

“The sort of changes that we as humans are bringing about could essentially be the same sort of catastrophic event that caused the Cretaceous-Tertiary mass extinctions. That took a while. This is probably faster.”

The study is published in the journal Science and was released yesterday at the International Coral Reef Symposium in Fort Lauderdale, Florida. The scientists said corals are now rated second only to amphibians as the most threatened group of animals on Earth. “The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds most terrestrial groups,” they added. Roger McManus, vice president of marine programmes at Conservation International, said that if sea-surface temperatures continue to rise, causing more frequent episodes of coral bleaching, it will be increasingly difficult for corals to survive further environmental insults.

“These results show that as a group, reef-building corals are more at risk of extinction than all terrestrial groups, apart from amphibians, and are the most vulnerable to the effects of climate change,” Dr McManus added. “The loss of corals will have profound implications for millions of people who depend on coral reefs for their livelihoods.”

Julia Marton-Lefevre, director general of the IUCN, said: “We either reduce CO2 emissions now or many corals will be lost forever. Improving water quality, global education and the adequate funding of local conservation practices are also essential to protect the foundation of beautiful and valuable coral reef ecosystems.”

Suggested Topics
Start your day with The Independent, sign up for daily news emails
PROMOTED VIDEO
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Sport
Ashley Barnes of Burnley scores their second goal
footballMan City vs Burnley match report
News
news
News
Sir James Dyson: 'Students must be inspired to take up the challenge of engineering'
i100
Life and Style
Apple showed no sign of losing its talent for product launches with the new, slightly larger iPhone 6 making headlines
techSecurity breaches and overhyped start-ups dominated a year in which very little changed (save the size of your phone)
Arts and Entertainment
Catherine (Sarah Lancashire) in Happy Valley ((C) Red Productions/Ben Blackall)
TV
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Sales Negotiator - OTE £24,000

£22000 - £24000 per annum: Recruitment Genius: An enthusiastic individual is r...

Recruitment Genius: Area Manager - West Midlands - OTE £35,000

£27000 - £30000 per annum: Recruitment Genius: An Area Manager is required to ...

Recruitment Genius: Area Manager - Yorkshire & Humber - OTE £35,000

£27000 - £30000 per annum: Recruitment Genius: An Area Manager is required to ...

Recruitment Genius: Embedded Linux Engineer - C / C++

£35000 - £45000 per annum: Recruitment Genius: A well funded smart home compan...

Day In a Page

A timely reminder of the bloody anniversary we all forgot

A timely reminder of the bloody anniversary we all forgot

Who remembers that this week we enter the 150th anniversary year of the end of the American Civil War, asks Robert Fisk
Homeless Veterans appeal: Former soldiers pay their respects to a friend who also served

Homeless Veterans appeal

Former soldiers pay their respects to a friend who also served
Downfall of Dustin 'Screech' Diamond, the 'Saved By The Bell' star charged with bar stabbing

Scarred by the bell

The downfall of the TV star charged with bar stabbing
Why 2014 was a year of technological let-downs

Why 2014 was a year of technological let-downs

Security breaches and overhyped start-ups dominated a year in which very little changed (save the size of your phone)
Cuba's golf revolution: But will the revolutionary nation take 'bourgeois' game to its heart?

Will revolutionary Cuba take 'bourgeois' golf to its heart?

Fidel Castro ridiculed the game – but now investment in leisure resort projects is welcome
The Locked Room Mysteries: As a new collection of the genre’s best is published, its editor Otto Penzler explains the rules of engagement

The Locked Room Mysteries

As a new collection of the genre’s best is published, its editor explains the rules of engagement
Amy Adams on playing painter Margaret Keane in Tim Burton's Big Eyes

How I made myself Keane

Amy Adams hadn’t wanted to take the role of artist Margaret Keane, because she’d had enough of playing victims. But then she had a daughter, and saw the painter in a new light
Ed Richards: Parting view of Ofcom chief. . . we hate jokes on the disabled

Parting view of Ofcom chief... we hate jokes on the disabled

Bad language once got TV viewers irate, inciting calls to broadcasting switchboards. But now there is a worse offender, says retiring head of the media watchdog, Ed Richards
A look back at fashion in 2014: Wear in review

Wear in review

A look back at fashion in 2014
Ian Herbert: My 10 hopes for sport in 2015. Might just one of them happen?

Ian Herbert: My 10 hopes for sport in 2015

Might just one of them happen?
War with Isis: The West needs more than a White Knight

The West needs more than a White Knight

Despite billions spent on weapons, the US has not been able to counter Isis's gruesome tactics, says Patrick Cockburn
Return to Helmand: Private Davey Graham recalls the day he was shot by the Taliban

'The day I was shot by the Taliban'

Private Davey Graham was shot five times during an ambush in 2007 - it was the first, controversial photograph to show the dangers our soldiers faced in Helmand province
Revealed: the best and worst airlines for delays

Revealed: the best and worst airlines for delays

Many flyers are failing to claim compensation to which they are entitled, a new survey has found
The stories that defined 2014: From the Scottish independence referendum to the Ice Bucket Challenge, our writers voice their opinions

The stories that defined 2014

From the Scottish independence referendum to the Ice Bucket Challenge, our writers voice their opinions
Stoke-on-Trent becomes first British city to be classified as 'disaster resilient' by the United Nations

Disaster looming? Now you know where to head...

Which British city has become the first to be awarded special 'resilience' status by the UN?