Mystery skin disease affecting whitetip reef sharks could be caused by rising sea temperatures

A mystery skin disease affecting whitetip reef sharks in Malaysia could be being caused by rising sea temperatures.

Named for the distinctive white tips on their fins, the sharks are typically found resting in schools around reefs in the day and are a popular attraction for divers.

They become active at night to hunt for small fish and other animals.

Pictures of one of the sharks with what appeared to be spots and lesions on its head went viral on social media in April after being taken by an underwater photographer off Sabah state on Borneo island.

Soon after, divers at Sipadan island, a famed diving destination nearby, and a team of experts from the state's university and government and conservation groups began seeing the skin disease in every group of sharks they encountered.

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Attempting to diagnose what could be causing the illness, the team found the sea surface temperature at Sipadan had risen to 29.5C (85.1F) in May, a degree higher than in 1985.

"We can almost certainly pin the warming ocean as having a role in what we are seeing with the sickly sharks in Sipadan," said Davies Austin Spiji, a senior marine biologist with conservation group Reef Guardian.

The reported sightings coincide with reports of coral bleaching in the area, according to Mohamed Shariff Mohamed Din, a professor in aquatic veterinary studies with Universiti Putra Malaysia.

"We cannot ignore that changes are happening there due to higher temperatures," Mohamed Shariff said.

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