This is the beautiful Samsae San Island in eastern Thailand.
But under these calm turquoise waters, a rapidly spreading disease, commonly known as yellow band disease, is killing coral over vast stretches of the sea floor.
The colour of the corals turns yellow before they get destroyed.
Scientists believe overfishing, pollution and rising water temperatures because of climate change may be making the reefs more vulnerable to yellow-band disease.
It was first spotted decades ago and has caused widespread damage to the reefs in the Caribbean. Over 600 acres of the sea have been infected.
Marine scientist Lalita Putchim says corals cannot remain alive when they are exposed to this yellow-band disease. They will die gradually.
The loss of coral could have a devastating impact on the ecosystem.
The reef is “like a forest” sustaining massive amounts of life, and its death could eventually impact humans too. They are rushing to find a treatment.
Researchers are using social media to track reports of infected reefs.
And they have also asked the public to report any sightings of the affected coral.
Voiceover: Abhinaya Sriram
Production: Reenu Cyriac
