Marine wildlife researchers have declared the unique dugong to be functionally extinct in Chinese waters.

BBC News reports on the study conducted by the Zoological Society of London and Chinese Academy of Science, which found that there have been no verified sightings of the aquatic mammal — a close relative of the manatee — for at least 22 years.

The dugong, which is believed to have inspired classic tales of mermaids, was classified as a key protected species in China in 1988 after decades of being hunted close to extinction.

But it’s believed that continued destruction of its inshore habitat — particularly the seagrass that make up the bulk of the vegetarian animal’s diet — has caused a "rapid population collapse”, researchers say.

BBC News has more on the story HERE.