The dugong — a marine mammal that purportedly inspired ancient mermaid tales — has been declared “functionally extinct” in China due to the degradation of its habitat caused by humans.
On Wednesday, a group of researchers from the Zoological Society of London (ZSL) and the Chinese Academy of Sciences published their findings in the peer-reviewed scientific journal Royal Society Open Science.
In their research article, the scientists explained that they conducted a large-scale interview survey across four Chinese provinces from July 15, 2019, to Aug. 13, 2019. The researchers also reviewed “all available historical data covering the past distribution of dugongs (Dugong dugon) in Chinese waters” for their research.
While investigating, they discovered that only 5% of 788 respondents reported previous dugong sightings, with the “mean last-sighting date” dating back 23 years. Three respondents claimed to have seen the marine mammal in the last five years.
Although previously recorded sightings of dugongs reached an all-time high around 1960, a decrease in sightings reportedly started in 1975. Scientists discovered that there have been no documented sightings of dugongs since 2008 and “no verified field observations after 2000.”
“Based on these findings, we are forced to conclude that dugongs have experienced rapid population collapse during recent decades and are now functionally extinct in China,” the research article read. “Our study provides evidence of a new regional loss of a charismatic marine megafaunal species, and the first reported functional extinction of a large vertebrate in Chinese marine waters.”
Dugong sightings in Chinese waters were reportedly recorded for hundreds of years. Countries bordering the South China Sea, such as Vietnam, Cambodia, Thailand, Malaysia, Brunei and the Philippines, all have historical records of dugong sightings as well.
Known to be the only strictly marine herbivorous mammal, the dugong has been classified as a Grade 1 National Key Protected Animal by China’s State Council since 1988 and is listed as globally vulnerable by the International Union for Conservation of Nature (IUCN). The dugong is particularly dependent on seagrass, which provides a habitat to marine animals.
The authors of the recent study believe that hunting combined with “the degradation of seagrass beds and accidental entanglement” have played a part in the decline of the dugong population in China’s waters.
“This rapid documented population collapse also serves as a sobering reminder that extinctions can occur before effective conservation actions are developed,” the authors noted.