The dugong, a gentle giant also known as a "sea cow," has disappeared from China, researchers say

The dugong, also known as a "sea cow," is extinct in China, scientists say. Researchers from Zoological Society of London and the Chinese Academy of Sciences say the gentle giant hasn't had a presence at all in China since 2008 and the latest research shows "strong indications that this is the first functional extinction of a large mammal in China's coastal waters," the society said in a press release.

The animal's population in China had been decreasing rapidly since the 1970s, with human activity, like fishing, threatening them. Being hit by ships and human-caused habitat loss also played a role in their decline.

The dugong was first designated for protection by the Chinese State Council in 1988. They were also listed as vulnerable by the International Union for Conservation and the society says they were one of the world's top mammal conservation priorities.

They have historically been found in the waters off East Africa to Vanuatu in the South Pacific Ocean and as far north as the southwestern islands of Japan. 

For the study, an international conservation team conducted interview surveys in 66 local finishing communities in four Chinese provinces along the South China Sea and reviewed historical data of dugong distribution. 

Out of 788 respondents, only 5% reported past dugong sightings – the average last-sighting date was 23 years ago. Only three respondents said they saw the dugong in 5 years. There are no verified field observations of the dugong after 2000, according to the study. 

The three recent dugong sightings collected during the study were from Shantou, China, but the area lacks the seagrass beds dugongs feed off of. This region is relatively close to the northern Philippines, which has a separate dugong population, so if dugongs were actually spotted there, they could have traveled from the Philippines.

Based on their findings the researchers said they were "forced to conclude that dugongs have experienced rapid population collapse during recent decades and are now functionally extinct in China."

The study is also a "sobering reminder" that extinctions can occur before effective conservation actions are developed.

Even individual dugongs still remain in Chinese waters, it is highly unlikely that the dramatic population decline with stop or be reversed under current conditions, so dugongs have little hope of even short-term survival in the region. 

While the researchers say they would "welcome any possible future evidence" that dugongs still exist, they are now recommending that the species' be classified as Critically Endangered (Possibly Extinct) in the region.

The dugong is a strictly herbivorous marine mammal – the only of its kind. The so-called sea cows are dependent upon sea grass, which is also being rapidly degraded by human impacts.  There are seagrass restoration efforts in China, but "restoration takes time that dugongs may no longer have" the society says. 

Professor Samuel Turvey of the society's Institute of Zoology called the likely disappearance of the dugong in China a "devastating loss."

"Their absence will not only have a knock-on effect on ecosystem function, but also serves as a wake-up call – a sobering reminder that extinctions can occur before effective conservation actions are developed," said Turvey, who co-authored the study. 

Turvey said the likely extinction of China's Yangtze River dolphin was documented in 2007 and this new study sadly shows once again "another charismatic aquatic mammal species in China" is likely extinct in the region "driven by unsustainable human activity."