Ghosting through the forests of Laos and Vietnam, the saola—a large ox that looks like an antelope—eluded researchers and their cameras for nearly 14 years.
But camera traps set out by the World Wildlife Fund (WWF) and the Vietnamese government in the central Annamite Mountains in Vietnam captured grainy black and white photographs of the extremely rare mammal in September of this year, the group announced this week.
The last sighting of a saola (Pseudoryx nghetinhensis) in the wild was in 1999 in Laos.
“When our team first looked at the photos we couldn’t believe our eyes,” said Van Ngoc Thinh, Vietnam’s country director for the WWF, in a statement. “Saola are the holy grail for south-east Asian conservationists so there was a lot of excitement.”
First discovered in 1992 near the border between Laos and Vietnam, the saola was the first large mammal new to science in more than 50 years, according to a WWF statement.
The mammal is often referred to as the “Asian unicorn” because of its rarity, although it sports two pointed horns on its head rather than one.
Although its elusive nature makes for a fun nickname, it has stymied researchers’ efforts to get a handle on the animal’s basic biology and population numbers.
Some estimates place global populations at 250 to 300 animals. But these are based on interviews with villagers who have seen the animal, and on hunting trophies, according to a report in Smithsonian magazine.
It’s incredibly difficult to measure the size of the saola population because conservationists do not have a full grasp on where they live, said Barney Long, the WWF director of species protection and Asian species conservation, in an interview this week.
One of the projects they’re working on to help detect this rare mammal in the field is by using leeches. “Southeast Asian land leeches drink blood from passing animals, and the blood stays in leeches for a few months,” he said. So researchers can test the blood to find out which animals the leech has been feeding on.
If saola blood turns up in a leech, the scientists will know the mammals are in the vicinity.
Listed as critically endangered in the IUCN Red List, saola often end up as incidental victims to snares set by hunters looking to catch Asiatic black bears or Malayan sun bears. The bears are hunted for their bile, which is used in traditional Chinese medicine. (See “Endangered Moon Bears Harvested for Bile in Vietnam.”)
Habitat fragmentation due mainly to road construction has also hammered saola populations.
The Vietnamese government has created nature preserves in the saola’s range, and banned all hunting in the mammal’s habitat in an effort to protect the animal.
“Since 2011, forest guard patrols in CarBi area have removed more than 30,000 snares from this critical saola habitat and destroyed more than 600 illegal hunters’ camps,” Van Ngoc in the statement. “Confirmation of the presence of the saola in this area is a testament to the dedicated and tireless efforts of these forest guards.”
Danielle Elliot assisted with reporting on this story.
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