Fishermen Catch Huge Numbers of Live Venomous Sea Snakes

 Journey to the Gulf of Thailand to witness the venomous sea snake trade with Emerging Explorer Zoltan Takacs.

Scientists sound a conservation alarm on the harvest of over 80 tons of sea snakes each year in the Gulf of Thailand.

By Jane J. Lee

National Geographic

 Fishermen wading barefoot through a writhing ball of venomous serpents can pay a high price for participating in the Gulf of Thailand's (map) sea snake harvest. Some die from snakebites, according to a recent study that suggests the snake catch may be one of the biggest hauls of marine reptiles in the world.

 Scientists published estimates of the catch size in the journal Conservation Biology in December, along with some of the first research documenting who's buying and selling sea snakes and the fishery's indirect role in rhino poaching

 Fishermen bitten by their deadly catch believe that drinking ground-up rhino horn—or putting chunks of horn on the wound—can cure them. (See "Why African Rhinos Are Facing a Crisis.")

Caught in the glare of artificial lights, these sea snakes are destined for dinner plates and use in traditional medicines.

Photograph by Zoltan Takacs

Some scientists are raising concerns about the practice. Little is known about the region's sea snakes, including what species and how many live there, so it's not clear whether the harvest is sustainable.

An overharvest, these researchers worry, could jeopardize potential medicinal discoveries. Compounds in venom, once processed and administered in controlled amounts, can be beneficial in treating human ailments like heart disease.

The sea snake catch—a side job for the region's Vietnamese squid fishers—takes in over 80 tons (73 metric tons) of the marine reptile annually. That's roughly 225,500 individual sea snakes per year, valued at over $3 million.

Fishermen bitten by sea snakes use treatments that contain rhinoceros horn (shown above), which has no proven medical benefits.

Photograph by Zoltan Takacs

The fishery of opportunity occurs during squid hunts conducted each lunar cycle before the moon gets too bright.

Most of the sea snakes end up in China and Vietnam, says the study's lead author Zoltan Takacs, whose work was funded by the National Geographic Society. Restaurants use the meat in soups and employ either the whole animal or just its blood in alcoholic beverages.

The snake's organs, including the heart and gallbladder, play central roles in concoctions meant to relieve maladies such as joint pain, anorexia, and insomnia.

Little is known about sea snakes in the Gulf of Thailand, so researchers aren't sure whether current harvest levels are sustainable.

Photograph by Zoltan Takacs

Lost Medicines?

Hunting snakes for food or medicinal purposes is nothing new, says John Murphy, a sea snake researcher at the Field Museum in Chicago. "[And] the Gulf of Thailand harvest seems to be driven by the Chinese market," says the biologist, who was not involved in the study.

Snakes figure prominently in traditional Chinese medicines, Murphy says. Coupled with the country's strong economy, "the demand for snakes—not just sea snakes—is huge." (See why "China's Expanding Middle Class Fuels Poaching, Decadence in Myanmar.")

Fishermen handle their highly venomous catch with little or no protection, often wading into pens barefoot and grabbing sea snakes with their bare hands.

Photograph by Zoltan Takacs

The demand extends to Western medical practices in other parts of the world, says Takacs, a pharmacologist specializing in animal toxins at ToxinTech in New York City.

"Out of the top three heart attack medications, two of them come from snake venoms," he says.

The potential uses of venoms in the sea snakes in the Gulf of Thailand haven't been studied, says Takacs. "So we absolutely have no idea what kind of venoms or toxins we are eating away."

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Sea snakes destined for market are sorted by weight and can fetch up to $20 per pound.

Photograph by Zoltan Takacs

News Source:http://news.nationalgeographic.com