Guardians of deadly vipers on China’s Snake Island

SHENYANG (XINHUA) – Off the coast of the Liaodong Peninsula in the Bohai Sea, there lies a beautiful island with turquoise waters, luscious jungles and an incredible coastline. But few dare set foot on this idyllic isle due to the mysterious locals – around 20,000 native venomous snakes.

Sun Lixin, 61, is an exception. Sun and his colleagues have guarded Shedao Island or Snake Island for almost four decades, saving the Shedao Island pit viper (Gloydius shedaoensis), a species endemic to the island, from extinction.

Sun’s efforts earned him the sobriquet ‘Snake Island Owner’.

Shedao Island pit vipers have survived natural selection but only narrowly escaped extinction due to threats such as food scarcity, poaching and habitat loss over the past several decades.

Covering an area of 73 hectares, the island is around 10km off the coast of Dalian, a city in northeast China.

As with other island serpents, the Shedao Island pit viper has developed a more potent venom to catch its main food source – migratory birds.

For generations, catching and eating birds had been a custom for local residents in the Laotie Mountain area, a stopover site for migratory birds near Snake Island.

“The pit viper’s diet consists mainly of migratory birds. So the number of birds directly affects the population of snakes. They are in a biological chain,” said former Deputy Director of Snake Island and the Laotie Mountain National Nature Reserve Administration Sun.

The Snake Island in Liaoning Province, northeast China. PHOTOS: XINHUA
Rangers patrol the Snake Island
A pit viper

Locals’ fondness for medicinal beverage also posed a threat to the snakes. From the 1960s to the 1970s, the business was booming on the island, which led to rampant poaching.

“With its potent venom, a Shedao Island pit viper can kill a bird in five minutes. Some people believed that drinking it could help cure disease, but there is no scientific basis to this. Nevertheless, these beliefs dealt a shattering blow to the snake population over the past century,” said Head of the administration’s Scientific Research Department Wang Xiaoping.

After the People’s Republic of China was founded in 1949, several surveys showed that there were 10,000 to 50,000 pit vipers on the island. In 1982, the number dropped to around 9,000, a record low. The venomous snakes were in imminent danger of extinction.

The snake species was listed as vulnerable on the International Union for Conservation of Nature’s Red List of Threatened Species. In 1980, China set up a national nature reserve covering Snake Island and the Laotie Mountain area to protect the unique pit vipers, migratory birds and surrounding environment.

The island and its adjacent waters are off-limits for tourists to prevent any harm to the snakes. However, a group of snake guardians have frequented the island in carrying out conservation and research work. Among those to blaze a trail was Sun Lixin.

Sun started working on the island soon after the nature reserve was established. One of the biggest challenges came in 1989 when Snake Island suffered three months of drought and the thirsty snakes were in critical condition.

Sun and his colleagues transported over 800 basins filled with water to the island via patrol ships. When they set the basins down, he was astonished to see the island was infested with countless snakes in search of water. The reserve staff later dug a well and built reservoirs to ease the water shortage.

There is a Chinese saying: “Once bitten by a snake, the mere sight of a rope will scare you for the rest of your life.” Sun has defied this by continuing to work with the snakes after being bitten more than 10 times. He has even become immune to snake venom.

But Sun and his colleagues have a healthy respect for the power of the vipers’ venom. “At first it just felt like being pricked with a needle, I didn’t feel like much at all. Two hours later when I arrived at the hospital, my arm had swollen right up, finally spreading down to my waist,” said Wang. “I’ve never felt anything so painful, the type of pain where you just want to cut your arm off.”

Yet despite their deadly power, the snakes have particularly fragile mouths, which are often hurt as they feed on the sharp beaks of migratory birds. The most common disease on the island is thus stomatitis. Snakes with oral cavity inflammation cannot open their mouths and often perish.

In such cases, the snake guardians double as veterinarians. They have to force the jaws of the poisonous snakes apart and treat their wounds with gentian violet.

“It’s inconvenient to wear gloves for this kind of work as the snakes’ mouths are too small,” Sun said. When he first set foot on the island, he was armed to the teeth with protective clothing, leg guards and a long stick. Now he dares to walk in the quivering grass in his slippers.

Life on Snake Island is not only risky but also lonely. In his busiest year, Sun spent over 240 days with the deadly snakes. He lived in a house with many cracks in the wall, allowing snakes to easily slither through at night, and the only source of entertainment was his radio.

Yet all of these challenges fail to dampen the guardians’ affection for the island and its cold-blooded dwellers. Over the past four decades, they have published nearly 100 thesis papers related to the pit vipers, and the snake population was stabilised at around 20,000 in the past decade.

With a core area of 3,565 hectares, the nature reserve only has 26 employees. It plans to introduce digital technologies in management, research and public environmental education, such as installing unmanned checkpoints and infrared cameras.

“We want to observe and study the life habits of pit vipers through infrared cameras. Currently, relevant software is being developed, and the work is expected to be completed next year,” said Director of the nature reserve’s administration Lin Xizhen.

In Lyushunkou District of Dalian, around 11km away from the nature reserve, stands a museum that tells the stories behind Snake Island. The reserve will upgrade its facilities and apply 3D imaging and multimedia technologies to offer a better viewing experience for visitors to the museum. It will also install LED screens in villages with a tradition of fowling, airing promotional videos on bird protection to educate the public.

Despite having retired, Sun joined a snake population survey in May. To measure the population density of snakes on the island, Sun captured over 200 snakes, marked their tails with non-toxic paint and then released them.

“My retirement was anything but a retreat. I hope more young people will join us to safeguard Snake Island, pit vipers and the natural environment,” Sun said.