Dugongs Declared 'Functionally Extinct' in China: What Happened to These Gentle Sea Cows?

Dugongs or sea cows are ocean mammals that were once mistaken for mermaids. But now, they have been declared "functionally extinct" in China after years of declining numbers due to human activities, such as fishing.

The new research, titled "Functional Extinction of Dugongs in China," published in the journal Royal Society Open Science, shows that their population in the Chinese seas started to dwindle in the 1970s, and by 2008, there are no records or evidence of dugong sightings in the South China Sea.

(Photo: Unsplash/Ray Aucott)
Dugongs Declared 'Functionally Extinct' in China: What Happened to These Gentle Sea Cows?

Decreasing Population of Dugongs Worldwide

Dugongs have rarely seen grazing on seagrass and swimming through oceans. According to MailOnline, sea cows are strictly herbivorous marine mammals that exclusively eat seagrass that can grow up to 10 feet (3 meters) long.

They were frequently seen in southern China for hundreds of years, in coastal waters from East Africa to Vanuatu, and in the southwestern islands of Japan. However, they are globally threatened, and the International Union for Conservation of Nature (IUCN) has listed them as vulnerable species.

Researchers of the new study interviewed 788 residents living in the coastal areas of China to find out if anyone of them had seen any dugongs in recent years. Their findings showed that it had been 23 years since anyone had seen the gentle giants of the sea, while only three people claimed they spotted one.

Dugongs can often be spotted close to the shore in shallow waters where they are also being hunted. In the 20th century, fishermen would capture dugongs for their bones, skin, and meat. Sea cows are one of the gentle giants of the sea and are the only herbivore marine mammal that makes them an easy target. Sometimes they are mistaken for manatees because of their whale-like tail and size.

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Human Activities Caused Dugong Extinction in China

The authors of the study said that they welcome any possible future evidence that dugongs might have survived in China. But for now, the study provides evidence of the probable regional loss of gentle marine mammals.

After surveying the residents in the coastal areas of China, Newsweek reported that the team initially thought that perhaps the dugongs could have moved north in response to human activities and climate change. Sadly, that is unlikely because of the lack of seagrass beds in the northern parts.

There are also no other dugong sightings or strandings in the area. Due to their findings, they recommend that the status of dugongs be changed to critically endangered or possibly extinct.

Professor Samuel Turvey from the Zoological Society of London's Institute of Zoology and co-author of the study told the news outlet that the extinction of sea cows in China could negatively impact the health of seagrass systems.

He pointed out that the disappearance of these marine mammals is due to human activities that progressively destroyed the seagrass beds in the South China Sea.

Dugongs are keystone species that help shape the marine ecosystem's structure. The study demonstrated that using ecological knowledge to understand the threatened biodiversity could be useful in reconstructing extinct dynamics. The team encourages other conservation studies to engage local communities to assess environmental requirements and possible threats to species.