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Several heatwaves in the Indian Ocean have killed more than two-thirds of corals in two years, a study has shown.

Research from the Zoological Society of London (ZSL) suggests some corals were more resilient to high temperatures, despite 70% of the hard corals in the ocean being lost between 2015 and 2017.

But, as these sorts of heatwaves become more frequent, the ability to recover will become “increasingly compromised”, the study says.

Seawater temperatures around the reefs in the Chagos Archipelago, part of the British Indian Ocean territory, were unusually high for eight weeks in 2015. Another heatwave hit the region before the corals could recover in 2016, this time lasting for four months.

The seafloor surveys before and after the heatwave saw the amount of healthy coral fall by 60% in 2015. Although scientists were unable to judge the impact of the 2016 heatwave across all the islands, data from the Peros Banhos atoll suggests that 70% of hard corals were lost due to the rise in temperature.

Coral bleaching affected the Archipelago in 1998. It took the reef ten years to recover, according to the study.
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Coral bleaching affected the Archipelago in 1998 and it took the reef 10 years to recover

But, while the second heatwave was longer, fewer of the surviving corals were killed.

Lead author of the study, Dr Catherine Head, a marine biologist at ZSL’s Institute of Zoology, said: “We know it has taken about 10 years for these reefs to recover in the past.

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“But, with global temperatures rising, severe heatwaves are becoming a more regular occurrence, which will hinder the reef’s ability to bounce back.”

She said preliminary reports from April 2019 suggested further high sea temperatures had led to more coral bleaching in the British Indian Ocean Territory, though it is not known yet how serious it is.

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“It is encouraging that reefs may have some degree of natural resilience, though further research is needed to understand the mechanisms by which some corals are able to protect themselves,” said Dr Head.

“This may be our best hope to save these vital habitats from the catastrophic effects of climate change.”

Similar coral death and changes to the reef’s make-up were seen in the Chagos Archipelago after global coral bleaching in 1998. Recovery took 10 years, according to the study.

The relatively fast recovery of the coral suggests the reef is highly resilient. It has also benefited from a lack of disturbance from humans, a result of the controversial removal of the Chagossian people by the UK in 1971 to make way for a US military base.

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Unhatched birds can warn other eggs in nest of danger by vibrating | Science & Tech News

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Unhatched baby seabirds can warn each other of impending danger by vibrating within their shells, scientists have discovered.

A study of yellow-legged gull embryos, found they reacted to warning calls from a parent and even passed on the message to siblings who had not heard the call.

The researchers collected gull eggs and divided them into groups of three.

A week before hatching, two of the three eggs in each nest were temporarily removed and exposed to a recording of a predator alarm call.

The noise was delivered four times a day at random intervals for three minutes at a time until hatching.

The third egg from each group remained in the nest in silence.

All three eggs were then reunited and left to hatch.

It was found the embryos responded to the external alarm calls by vibrating more.

This information appeared to be passed on to the third egg which had not been directly exposed to the sounds and it then mimicked the vibrations.

Experts from the Animal Ecology Group at the University of Vigo in Spain discovered all the chicks underwent genetic changes that delayed hatch time.

There was also evidence of increased production of stress hormones which is known to make birds more aware of their surroundings after hatching.

The findings were published in the journal, Nature Ecology and Evolution.

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Bali arrests: Shackled Australians facing jail over ‘cocaine use’ | World News

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Two Australian men have been paraded in front of the media a week after being arrested in Bali on suspicion of cocaine use and possession.

Indonesian police are preparing to charge the pair and are currently searching for a third suspect after a series of drug raids in the village of Canggu, a popular nightclub area on the island of Bali.

The two men, who have been named as William Cabantong, 35, and David Van Iersel, 38, were led out in front of the media in hand and foot shackles, alongside local drug suspects.

Police acted on a tip-off, and said they found 1.12g of cocaine in the pockets of one of the men, as well as drug equipment including a set of broken scales.

The men bought 2g of cocaine for three million rupiahs (£172), according to police.

The pair have undergone days of interrogation and tests while in prison. Police say a blood test revealed that both Mr Cabantong and Mr Van Iersel were cocaine users.

Denpasar police chief Ruddi Setiawan told reporters: “We advise tourists, locals, and foreigners to come here for a holiday, don’t come to have a drugs party or to use drugs.

“We will take firm action if any foreigners resist. We will not be lenient.”

The men are expected to be charged under Indonesian law 112, legislation which covers drug possession. The punishment carries a possible jail term of between four and 12 years, as well as a fine of 800 million rupiah (£45,000).

The men hid their faces as they stood with others arrested on drug charges
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The men hid their faces as they stood with others arrested on drug charges

It is understood that both Mr Cabantong and Mr Van Iersel worked as nightclub promoters whilst they lived in Australia before they travelled to Bali.

Indonesia is known for its strong penalties against those who commit drug offences. In 2017, Indonesian President Joko Widodo told police officers to shoot drug traffickers.

He said: “Be firm, especially to foreign drug dealers who enter the country and resist arrest. Shoot them because we indeed are in a narcotics emergency position now.”

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Drug-resistant malaria strains spread through south east Asia | World News

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Strains of drug-resistant malaria are becoming more dominant in Vietnam, Laos and northern Thailand after spreading rapidly from Cambodia.

Malaria is caused by parasites which are carried by mosquitoes and spread through their blood-sucking bites.

And scientists have discovered a growing number of cases where the parasite has mutated making it resistant to drugs.

“We discovered (it) had spread aggressively, replacing local malaria parasites, and had become the dominant strain in Vietnam, Laos and northeastern Thailand,” said Roberto Amato, from the Wellcome Sanger Institute.

Malaria can be successfully treated with medicines if it is caught early enough, but resistance to anti-malarial drugs is growing in many parts of the world, especially in south east Asia.

The first-line treatment for malaria in many parts of Asia in the last decade has been a combination of dihydroartemisinin and piperaquine, also known as DHA-PPQ.

Researchers found in previous work that a strain of malaria had evolved and spread across Cambodia between 2007 and 2013 that was resistant to both drugs.

This latest research, published in The Lancet Infectious Diseases journal, found it has crossed borders and tightened its grip.

“The speed at which these resistant malaria parasites have spread in south east Asia is very worrying,” said Olivo Miotto, who co-led the work.

“Other drugs may be effective at the moment but the situation is extremely fragile and this study highlights that urgent action is needed.”

Almost 220 million people were infected with malaria in 2017, according to World Health Organisation estimates, and the disease killed 400,000 of them.

The vast majority of cases and deaths are among babies and children in sub-Saharan Africa.

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