Researchers trying to find the causes of coral bleaching that has devastated reefs around the world have identified a virus that may be responsible.

It is believed to be naturally present in symbiotic algae within corals, but with temperatures and levels of ultraviolet light increasing because of global warming it is multiplying, with deadly effect.

The algae that provide the corals with carbohydrates and sugars die, leaving the corals too weak to prevent larger algal lifeforms smothering the reefs.

An estimated 30 per cent of corals are expected to disappear in the next 30 years, with bleaching playing a major role.

Microbiologists at the University of Plymouth used electron microscopy images to study and name the virus as ZFV1, with their findings published in the journal Applied and Enviromental Microbiology. The virus was identified by Jayme Lohr, a Phd student.

Dr Colin Munn, of the University of Plymouth, said “This could explain how climate change alone is not responsible for the destruction of coral reefs.”

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