By Environment Correspondent Alister Doyle

OSLO, March 24 (Reuters) - Climate change is likely to make reef-building stony corals lose out to softer cousins in a damaging shift for many types of fish that use reefs as hideaways and nurseries for their young, a study showed.

Soft corals such as mushroom-shaped yellow leather coral, which lack a hard outer skeleton, were far more abundant than hard corals off Iwotorishima, an island off south Japan where volcanic vents make the waters slightly acidic, it said.

A build-up of carbon dioxide in the atmosphere is turning the oceans more acidic in a process likely to hamper the ability of creatures such as lobsters, crabs, mussels or stony corals to build protective outer layers.

"Soft coral has the potential to be a winner in coral reefs," lead author Shihori Inoue of the University of Tokyo told Reuters by e-mail of the findings, the first study of likely winners and losers among soft and hard corals.

"Reef communities may shift from reef-building hard corals to non-reef-building soft corals under (carbon dioxide levels) predicted by the end of this century," the authors wrote in Monday's edition of the journal Nature Climate Change.

When it reacts with water, carbon dioxide in the atmosphere can form carbonic acid. That damages hard corals, tiny animals that secrete calcium carbonate to form their stony protective layer.

"When combined with their ability for rapid colonisation, soft corals may out compete hard corals in coral reef environments subject to ocean acidification," the scientists wrote.


CLOWNFISH

"Hard corals are important reef builders and provide complex three-dimensional habitats for many reef organisms," they wrote, adding that a shift could have damaging effects for many fish and other marine creatures that live around reefs.

A community of soft coral "hardly works like hard coral as a nest for small living organism such as ... shrimp, and little fish," Inoue said. The 2003 animated movie "Saving Nemo" shows how clownfish live and grow around reefs.

Covering less than one percent of the ocean floor, reefs support about 25 percent of all marine life, with over 4,000 species of fish alone, according to the International Coral Reef Initiative which seeks to protect reefs.

The scientists said that the levels of carbon dioxide in the water off Iwotorishima, an island near Okinawa in the Pacific, corresponded varied from equivalent to 550 parts per million (ppm) of carbon dioxide in the atmosphere to as high as 970. Both levels are within the range seen as possible by 2100 according to the U.N. panel of climate scientists.

Current atmospheric levels are about 395 ppm, a sharp rise from 280 ppm before the Industrial Revolution. And emissions of carbon dioxide are continuing to rise - China, the United States and the European Union are the top emitters.

Other studies have also shown that stony coral reefs are vulnerable to rises in temperature that can cause a whitening that can lead to death.

Gas vents in the Mediterranean and corals around a carbon dioxide seep off Papua New Guinea have also been used to study the likely future conditions of the oceans.

"Soft coral may not always be the winner in acidified waters. In temperate oceans, it has been shown that algae or sea anemones can be winners at high-carbon dioxide vents," they wrote. (Reporting by Alister Doyle; Editing by Jason webb)

CORRECTION: A previous version of this entry's headline misidentified which type of coral is likely to be most impacted by climate change.

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  • <strong>Scientific Name:</strong> <em>Diceros sumatrensis</em> <strong>Common Name: </strong>Sumatran rhino <strong>Category:</strong> Rhino <strong>Population: </strong> < 250 individuals <strong>Threats To Survival:</strong> Hunting for horn -used in traditional medicine

  • <strong>Scientific Name:</strong> <em>Eleutherodactylus thorectes</em> <strong>Common Name: </strong>Macaya Breast-Spot Frog <strong>Category:</strong> Frog <strong>Population: </strong>Unknown <strong>Threats To Survival:</strong> Habitat destruction due to charcoal production and slash-and-burn agriculture Credit: <a href="http://www.robindmoore.com">Robin Moore</a>

  • <strong>Scientific Name:</strong> <em>Scaturiginichthys vermeilipinnis</em> <strong>Common Name: </strong>Red-Finned Blue Eye <strong>Category:</strong> Freshwater Fish <strong>Population: </strong>2,000 - 4,000 Individuals <strong>Threats To Survival:</strong> Predation by introduced species

  • <strong>Scientific Name:</strong> <em>Rafetus Swinhoei</em> <strong>Common Name: </strong>Red River Giant Softshell Turtle <strong>Category:</strong> Turtle <strong>Population: </strong>4 known individuals <strong>Threats To Survival:</strong> Hunting for consumption and habitat destruction and degradation as a result of wetland destruction and pollution

  • <strong>Scientific Name:</strong> <em>Neurergus kaiseri</em> <strong>Common Name: </strong>Luristan newt <strong>Category:</strong> Newt <strong>Population: </strong> < 1000 mature individuals <strong>Threats To Survival:</strong> Illegal collection for pet trade

  • List Provided By Zoological Society Of London/ International Union For Conservation Of Nature

    <strong>Scientific Name:</strong> <em>Poecilotheria metallica</em> <strong>Common Name: </strong>Peacock Parachute Spider <strong>Category:</strong> Spider <strong>Population: </strong>Unknown <strong>Threats To Survival:</strong> Habitat loss and degradation as a result of deforestation, firewood collection and civil unrest

  • <strong>Scientific Name:</strong> <em>Atelopus balios</em> <strong>Common Name: </strong>Rio Pescado Stubfoot Toad <strong>Category:</strong> Toad <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Chytridiomycosis and habitat destruction due to logging and agricultural expansion

  • <strong>Scientific Name:</strong> <em>Johora Singaporensis</em> <strong>Common Name: </strong>Singapore Freshwater Crab <strong>Category:</strong> Crab <strong>Population: </strong>Unknown <strong>Threats To Survival:</strong> Habitat degradation - reduction in water quality and quantity

  • <strong>Scientific Name:</strong> <em>Abies beshanzuensis</em> <strong>Common Name: </strong>Baishan Fir <strong>Category:</strong> Conifer <strong>Population: </strong>5 mature individuals <strong>Threats To Survival:</strong> Agricultural expansion and fire

  • <strong>Scientific Name:</strong> <em>Actinote zikani </em> <strong>Common Name: </strong>None <strong>Category:</strong> Butterfly <strong>Population: </strong>Unknown, one population remaining <strong>Threats To Survival:</strong> Habitat degradation due to pressure from human populations

  • <strong>Scientific Name:</strong> <em>Aipysurus foliosquama</em> <strong>Common Name: </strong>Leaf Scaled Sea-Snake <strong>Category:</strong> Sea snake <strong>Population: </strong> Unknown, two subpopulations remain <strong>Threats To Survival:</strong> Unknown - likely degradation of coral reef habitat

  • <strong>Scientific Name:</strong> <em>Amanipodagrion gilliesi</em> <strong>Common Name: </strong>Amani Flatwing <strong>Category:</strong> Damselfly <strong>Population: </strong> < 500 individuals est. <strong>Threats To Survival:</strong> Habitat degradation due to increasing population pressure and water pollution

  • <strong>Scientific Name:</strong> <em>Antilophia bokermanni</em> <strong>Common Name: </strong>Araripe Manakin <strong>Category:</strong> bird <strong>Population: </strong>779 individuals (est 2010) <strong>Threats To Survival:</strong> Habitat destruction due to expansion of agriculture and recreational facilities and water diversion

  • <strong>Scientific Name:</strong> Antisolabis seychellensis <strong>Common Name: </strong> Seychelles Earwig <strong>Category:</strong> Earwig <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Invasive species and climate change

  • <strong>Scientific Name:</strong> Aphanius transgrediens <strong>Common Name: </strong>None <strong>Category:</strong> Freshwater fish <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Competition and predation by Gambusia and road construction

  • <strong>Scientific Name:</strong> Ardeotis nigriceps <strong>Common Name: </strong> Great Indian Bustard <strong>Category:</strong> Bird <strong>Population: </strong> 50 -249 mature individuals <strong>Threats To Survival:</strong> Habitat loss and modification due to agricultural development

  • <strong>Scientific Name:</strong> Aproteles bulmerae <strong>Common Name: </strong>Bulmer's Fruit Bat <strong>Category:</strong> Bat <strong>Population: </strong>150 individuals (est) <strong>Threats To Survival:</strong> Hunting and cave disturbance

  • <strong>Scientific Name:</strong> Ardea insignis <strong>Common Name: </strong>White Bellied Heron <strong>Category:</strong> Bird <strong>Population: </strong>70-400 individuals <strong>Threats To Survival:</strong> Habitat destruction and degradation due to hydropower development

  • <strong>Scientific Name:</strong> <em>Astrochelus yniphora</em> <strong>Common Name: </strong> Ploughshare Tortoise / Angonoka <strong>Category:</strong> Tortoise <strong>Population: </strong>440-770 <strong>Threats To Survival:</strong> Illegal collection for international pet trade

  • <strong>Scientific Name:</strong> <em>Aythya innotata</em> <strong>Common Name: </strong>Madagascar Pochard <strong>Category:</strong> Bird <strong>Population: </strong> Approximately 20 mature individuals <strong>Threats To Survival:</strong> Habitat degradation due to slash-and-burn agriculture, hunting, and fishing / introduced fish

  • <strong>Scientific Name:</strong> <em>Azurina eupalama</em> <strong>Common Name: </strong> Galapagos damsel fish <strong>Category:</strong> Pelagic fish <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Climate Change - oceanographic changes associated with the 1982 / 1983 El Nino are presumed to be responsible for the apparent disappearance of this species from the Galapagos

  • <strong>Scientific Name:</strong> <em>Bahaba taipingensis</em> <strong>Common Name: </strong> Giant yellow croaker <strong>Category:</strong> Pelagic fish <strong>Population: </strong> Unknown (declining) <strong>Threats To Survival:</strong> Over-fishing, primarily due to value of swim-bladder for traditional medicine - cost per kilogram exceeded that of gold in 2001

  • <strong>Scientific Name:</strong> <em>Batagur baska</em> <strong>Common Name: </strong> Common Batagur/ Four-toed terrapin <strong>Category:</strong> Turtle <strong>Population: </strong> Unknown (declining) <strong>Threats To Survival:</strong> Illegal export and trade from Indonesia to China

  • <strong>Scientific Name:</strong> Bazzania bhutanica <strong>Common Name: </strong>None <strong>Category:</strong> Liverwort <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Habitat degradation and destruction due to forest clearance, overgrazing and development

  • <strong>Scientific Name:</strong> <em>Beatragus hunteri</em> <strong>Common Name: </strong>Hirola <strong>Category:</strong> Antelope <strong>Population: </strong> < 1000 individuals <strong>Threats To Survival:</strong> Habitat loss and degradation, competition with livestock, poaching

  • <strong>Scientific Name:</strong> <em>Bombus franklinii</em> <strong>Common Name: </strong>Franklin's Bumble Bee <strong>Category:</strong> Bee <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Disease from commercially bred bumblebees and habitat destruction and degradation

  • <strong>Scientific Name:</strong> Brachyteles hypoxanthus <strong>Common Name: </strong> Northern muriqui <strong>Category:</strong> Primate <strong>Population: </strong> < 1,000 individuals <strong>Threats To Survival:</strong> Habitat loss and fragmentation due to large-scale deforestation and selective logging

  • <strong>Scientific Name:</strong> <em>Bradypus pygmaeus</em> <strong>Common Name: </strong>Pygmy sloth <strong>Category:</strong> Sloth <strong>Population: </strong> < 500 individuals <strong>Threats To Survival:</strong> Habitat loss due to illegal logging of mangrove forests for firewood and construction and hunting of the sloths

  • <strong>Scientific Name:</strong> <em>Callitriche pulchra</em> <strong>Common Name: </strong>None <strong>Category:</strong> Freshwater plant <strong>Population: </strong> Unknown (declining) <strong>Threats To Survival:</strong> Exploitation of the species' habitat by stock, and modification of the pool by local people

  • <strong>Scientific Name:</strong> <em>Calumma tarzan</em> <strong>Common Name: </strong>Tarzan's Chameleon <strong>Category:</strong> Chameleon <strong>Population: </strong>Unknown <strong>Threats To Survival:</strong> Habitat destruction for agriculture

  • <strong>Scientific Name:</strong> <em>Cavia intermedia</em> <strong>Common Name: </strong>Santa Catarina's Guinea Pig <strong>Category:</strong> Guinea Pig <strong>Population: </strong> 40-60 individuals <strong>Threats To Survival:</strong> Habitat disturbance and possible hunting; small population effects

  • <strong>Scientific Name:</strong> <em>Cercopithecus roloway</em> <strong>Common Name: </strong>Roloway Guenon <strong>Category:</strong> Primate <strong>Population: </strong>Unknown <strong>Threats To Survival:</strong> Hunting for consumption as bushmeat, and habitat loss

  • <strong>Scientific Name:</strong> <em>Coleura seychellensis</em> <strong>Common Name: </strong>Seychelles Sheath-Tailed Bat <strong>Category:</strong> Bat <strong>Population: </strong> < 100 mature individuals (est 2008) <strong>Threats To Survival:</strong> Habitat degradation and predation by invasive species

  • <strong>Scientific Name:</strong> <em>Cryptomyces maximus</em> <strong>Common Name: </strong>None <strong>Category:</strong> Fungus <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Limited availability of habitat

  • <strong>Scientific Name:</strong> <em>Cryptotis nelsoni</em> <strong>Common Name: </strong>Nelson's Small-Eared Shrew <strong>Category:</strong> Shrew <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> habitat loss due to logging cattle grazing, fire and agriculture

  • <strong>Scientific Name:</strong> <em>Cyclura collei</em> <strong>Common Name: </strong>Jamaican Iguana <strong>Category:</strong> Iguana <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Predation by introduced species and habitat destruction

  • <strong>Scientific Name:</strong> <em>Dendrophylax fawcettii</em> <strong>Common Name: </strong>Cayman Islands Ghost Orchid <strong>Category:</strong> Orchid <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Habitat destruction due to infrastructure development

  • <strong>Scientific Name:</strong> <em>Diomedea amsterdamensis</em> <strong>Common Name: </strong>Amsterdam Island Albatross <strong>Category:</strong> Bird <strong>Population: </strong>100 mature individuals <strong>Threats To Survival:</strong> Disease and incidental capture in long-line fishing operations

  • <strong>Scientific Name:</strong> <em>Diospyros katendei</em> <strong>Common Name: </strong> None <strong>Category:</strong> Tree <strong>Population: </strong>20 individuals, one population <strong>Threats To Survival:</strong> High pressure from communities for agricultural activity, illegal tree felling, habitat degradation due to alluvial gold digging and small population

  • <strong>Scientific Name:</strong> <em>Dipterocarpus lamellatus</em> <strong>Common Name: </strong>None <strong>Category:</strong> Dipterocarp (tree) <strong>Population: </strong>12 individuals <strong>Threats To Survival:</strong> Habitat loss and degradation due to logging of lowland forest and creation of industrial plantations

  • <strong>Scientific Name:</strong> <em>Discoglossus nigriventer</em> <strong>Common Name: </strong> Hula painted frog <strong>Category:</strong> Frog <strong>Population: </strong>Unknown (recent rediscovery in 2011) <strong>Threats To Survival:</strong> Predation by birds and range restriction due to habitat destruction

  • <strong>Scientific Name:</strong> <em>Discorea strydomiana</em> <strong>Common Name: </strong>Wild Yam <strong>Category:</strong> Yam <strong>Population: </strong>200 Individuals <strong>Threats To Survival:</strong> Collection for medicinal use

  • <strong>Scientific Name:</strong> <em>Dombeya mauritiana</em> <strong>Common Name: </strong>None <strong>Category:</strong> Flowering plant <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Habitat degradation and destruction due to encroachment by alien invasive plant species and cannabis cultivation

  • <strong>Scientific Name:</strong> <em>Eleocarpus bojeri</em> <strong>Common Name: </strong>None <strong>Category:</strong> Flowering plant <strong>Population: </strong> < 10 individuals <strong>Threats To Survival:</strong> Small population and degraded habitat

  • <strong>Scientific Name:</strong> <em>Eleutherodactylus glandulifer</em> <strong>Common Name: </strong>La Hotte Glanded Frog <strong>Category:</strong> Frog <strong>Population: </strong>Unknown (declining) <strong>Threats To Survival:</strong> Habitat destruction due to charcoal production and slash-and-burn agriculture

  • <strong>Scientific Name:</strong> <em>Eriosyce chilensis</em> <strong>Common Name: </strong>Chilenito <strong>Category:</strong> Cactus <strong>Population: </strong> < 500 individuals <strong>Threats To Survival:</strong> Collection of flowering individuals

  • <strong>Scientific Name:</strong> <em>Erythrina schliebenii</em> <strong>Common Name: </strong>Coral Tree <strong>Category:</strong> Flowering tree <strong>Population: </strong> < 50 individuals <strong>Threats To Survival:</strong> Limited habitat and small population size increasing vulnerability to stochastic events

  • <strong>Scientific Name:</strong> <em>Euphorbia tanaensis</em> <strong>Common Name: </strong>None <strong>Category:</strong> Semi-deciduous tree <strong>Population: </strong>4 mature individuals <strong>Threats To Survival:</strong> Illegal logging and habitat degradation due to agricultural expansion and infrastructure development

  • <strong>Scientific Name:</strong> <em>Eurynorhynchus pygmeus</em> <strong>Common Name: </strong>Spoon-Billed Sandpiper <strong>Category:</strong> Bird <strong>Population: </strong> < 100 breeding pairs <strong>Threats To Survival:</strong> Trapping on wintering grounds and land reclamation.

  • <strong>Scientific Name:</strong> <em>Ficus katendei</em> <strong>Common Name: </strong>None <strong>Category:</strong> Tree (ficus) <strong>Population: </strong> < 50 mature individuals <strong>Threats To Survival:</strong> Agricultural activity, illegal tree felling and habitat degradation due to alluvial gold digging

  • <strong>Scientific Name:</strong> <em>Geronticus eremita</em> <strong>Common Name: </strong>Northern Bald Ibis <strong>Category:</strong> Bird <strong>Population: </strong>200-249 mature individuals <strong>Threats To Survival:</strong> Habitat degradation and destruction, and hunting