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Deep-sea coral reefs
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Researchers make improbable discovery of deep-sea coral reefs in "hostile" Pacific Ocean depths

Scientists had long believed that the waters of the Central and Northeast Pacific Ocean were inhospitable to certain species of deep-sea corals, but a marine biologist's discovery of an odd chain of reefs suggests there are mysteries about the development and durability of coral colonies yet to be uncovered.
Scientist Amy Baco-Taylor of Florida State University (FSU), in collaboration with researchers from Texas A&M University, found the reefs during an autonomous underwater vehicle survey of the seamounts of the Northwestern Hawaiian Islands.
In a paper published today in the journal Scientific Reports, Baco-Taylor and her team document the reefs. They also discuss possible explanations for the reefs' appearance in areas considered hostile to large communities of scleractinia -- small, stony corals that settle on the seabed and grow bony skeletons to protect their soft bodies.

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RE: Coral reefs
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How fossil corals can shed light on the Earth's past climate

In a paper published today in Science, researchers from the University of Bristol describe how they used radiocarbon measured in deep-sea fossil corals to shed light on carbon dioxide (CO2) levels during the Earths last deglaciation.
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Geologists to Solve Evolutionary Mystery of Corals

One of the greatest mysteries of modern coral reefs is how they evolved from ancient corals. A critical knowledge gap has long existed in the record of coral evolution. This evolutionary gap occurs during a period of dramatic fluctuations in sea level and changes in the Earth's climate between 1 and 2 million years ago. During this period many "old" corals went extinct, and the modern reef corals emerged.
To fill this key temporal gap and understand the evolutionary and ecological transition to modern Caribbean reefs, the National Science Foundation (NSF) has funded a University of Miami (UM) research team to study corals along the southern coast of the Dominican Republic. It is one of the few areas that contain a record of coral reefs from this period of climatic change.

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Findings from a "natural laboratory" in seas off Papua New Guinea suggest that acidifying oceans will severely hit coral reefs by the end of the century.
Carbon dioxide bubbles into the water from the slopes of a dormant volcano here, making it slightly more acidic.
Coral is badly affected, not growing at all in the most CO2-rich zone.

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Title: Growth rate and age distribution of deep-sea black corals in the Gulf of Mexico
Authors: N. G. Prouty, E. B. Roark, N. A. Buster, S. W. Ross

Black corals (order Antipatharia) are important long-lived, habitat-forming, sessile, benthic suspension feeders that are found in all oceans and are usually found in water depths greater than 30 m. Deep-water black corals are some of the slowest-growing, longest-lived deep-sea corals known. Previous age dating of a limited number of black coral samples in the Gulf of Mexico focused on extrapolated ages and growth rates based on skeletal 210Pb dating. Our results greatly expand the age and growth rate data of black corals from the Gulf of Mexico. Radiocarbon analysis of the oldest Leiopathes sp. specimen from the upper De Soto Slope at 300 m water depth indicates that these animals have been growing continuously for at least the last 2 millennia, with growth rates ranging from 8 to 22 m yr^-1. Visual growth ring counts based on scanning electron microscopy images were in good agreement with the 14C-derived ages, suggestive of annual ring formation. The presence of bomb-derived 14C in the outermost samples confirms sinking particulate organic matter as the dominant carbon source and suggests a link between the deep-sea and surface ocean. There was a high degree of reproducibility found between multiple discs cut from the base of each specimen, as well as within duplicate subsamples. Robust 14C-derived chronologies and known surface ocean 14C reservoir age constraints in the Gulf of Mexico provided reliable calendar ages with future application to the development of proxy records.

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Acropora palmata
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Super-rare 'elkhorn' coral found in Pacific

An Australian scientist has discovered what could be the world's rarest coral in the remote North Pacific Ocean.
The unique Pacific elkhorn coral was found while conducting underwater surveys of Arno atoll in the Marshall Islands, by coral researcher Dr Zoe Richards of the ARC Centre of Excellence for Coral Reef Studies (CoECRS).
The coral bears a close physical resemblance to the critically endangered and fast-vanishing elkhorn coral (Acropora palmata) of the Atlantic Ocean, but genetic analysis has shown it to be a different species.

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RE: Coral reefs
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Scientists have reported a rapid recovery in some of the coral reefs that were damaged by the Indian Ocean tsunami four years ago.
It had been feared that some of the reefs off the coast of Indonesia could take a decade to recover.
The New York-based Wildlife Conservation Society (WCS) found evidence of rapid growth of young corals in badly-hit areas.
A spokesman said reefs damaged before the tsunami were also recovering.

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Coral reefs found growing in cold, deep ocean
Imagine descending in a submarine to the ice-cold, ink-black depths of the ocean, 800 metres under the surface of the Atlantic. Here the tops of the hills are covered in large coral reefs. NIOZ-researcher Furu Mienis studied the formation of these unknown cold-water relatives of the better-known tropical corals.
Furu Mienis studied the development of carbonate mounds dominated by cold-water corals in the Atlantic Ocean at depths of six hundred to a thousand metres. These reefs can be found along the eastern continental slope from Morocco to Norway, on the Mid-Atlantic Ridge and on the western continental slope along the east coast of Canada and the United States. Mienis studied the area to the west of Ireland along the edges of the Rockall Trough.

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Coral climate recorders
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Coral skeletons can reveal facts of climate change

"Corals are natural climate recorders. They grow continuously, so there are no gaps in the record. And they grow for a long time, sometimes reaching 1,000 years old" - Anne Cohen, WHOI Research Associate.

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New theory of corals' ability to adapt to climate change
A new CReefs paper, published in the leading evolutionary journal, The American Naturalist, reported on the potential for corals to evolve greater resistance to bleaching. The joint study, carried out by scientists from Queen's University in Canada and the Australian Institute of Marine Science presented a new way of examining how coral reefs may respond to climate change.
The research did not indicate that corals are safe from climate change, but rather provided a framework for assessing the potential for corals to evolve a greater ability to cope with climate-induced changes.

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