Deep in the forests of Vietnam, scientists are patiently waiting to catch sight of the silver-backed chevrotain. The creature in question hasn’t been seen for nearly 30 years and is so rare that scientists fear it could be almost extinct. But just when it seems that all hope might be lost, a movement in the woods triggers a camera trap.
You may not have heard of the silver-backed chevrotain. Also known as the Tragulus versicolor – or Vietnamese mouse-deer – it was first described by the British zoologist Oldfield Thomas in 1910 when four specimens were found near the southern Vietnamese city of Nha Trang. However, they have since proved pretty elusive as a species.
Back when the silver-backed chevrotain was discovered, scientists noted a unique slate-gray sheen running along its rump. This – along with some distinctive markings on the throat – set the species apart from the more prevalent lesser chevrotain. However, after these initial sightings, the trail on the animal went cold.
For decades, little was known about the silver-backed chevrotain. The information we did have on the creature was a description of its appearance. The mysterious animal resembles a small deer, but it is no bigger than a rabbit. And it sports distinctive two-tone fur which results in a silvery sheen.
Given the unusual appearance of the silver-backed chevrotain, it’s perhaps easy to see how the animal earned its “Vietnamese mouse-deer” nickname. But it’s not actually related to either of these two creatures. Instead, they are ungulates – or hoofed animals. And they weigh less than 10 pounds, which makes them the smallest of their species in the world.
One particularly curious thing about the appearance of the silver-backed chevrotain is its tusk-like incisors. These are particularly long in males. Given the fact that chevrotains have no antlers or horns, it’s believed that they may use these fangs when competing for mates and territory.
The few specimens of the silver-backed chevrotain that scientists have obtained were found in the coastal forests near Nha Trang. It’s been theorized that the animals prefer dry habitats like thorn scrubs as opposed to Vietnam’s wetter tropical forests. That’s because they have never actually been spotted in the latter.
The dry habitats that the silver-backed chevrotain has been found in are a rarity in the region. Andrew Tilker is a biologist that specializes in the wildlife of Southeast Asia, and he talked about the animal’s surroundings in a 2019 interview with National Geographic. He said, “Although such forests are not common, there are parts of Vietnam that remind me of my home state of Texas.”
But while scientists believe that they may have narrowed down a habitat for the silver-backed chevrotain, the creature remained illusive. After the initial specimens of the animal were obtained, there were no more sightings for 80 years, when Russian scientists seized a further example from Vietnamese hunters.
The Russian-obtained silver-backed chevrotain proved to be a one-off though. And for nearly three decades there were no further sightings of the animal. As a result, little is known about the unusual creature. This makes it one of scientists’ “most wanted” animals in the world alongside similarly evasive species – such as Attenborough’s long-beaked echidna and the Pondicherry shark.
When it comes to so-called “lost” species like the silver-backed chevrotain, conservationists know very little. It’s not even clear where such creatures can be found, let alone how many of them are left in existence. With that in mind, the International Union for the Conservation of Nature lists the silver-backed chevrotain as “data deficient.” That’s because there is not enough information to determine if they’re extinct, endangered or otherwise.
Because scientists know so little about the silver-backed chevrotain, it’s not clear what kind of threats they face or how to protect them. It’s believed that the animals may be preyed upon by pythons, wild dogs and leopards. However, there’s also some fear that they fall victim to snares left by hunters.
So, in the nearly 30 years that followed the last sighting of a silver-backed chevrotain, there was some fear that the animal may have been pushed close to extinction. As a result, the race was on to locate the lost species before it was too late. That’s where Global Wildlife Conservation stepped in – adding the creature to its list of the 25 “most wanted” creatures.
Global Wildlife Conservation is an organization that works to retain and restore biodiversity. Its work is particularly focused on the forgotten animals that are facing extinction but are often overlooked. And it is also concerned with locating lost species like the silver-backed chevrotain.
The group has put together a list of 1,200 types of plants and animals that have become missing to science. They have gone unseen for a number of years, and could potentially be close to extinction. So, in order to save these species, the Global Wildlife Conservation organization set out to locate them.
In order to find the lost species, Global Wildlife Conservation teamed up with over 100 scientists to scour some of the world’s most remote locations. These included the dry coastal forests near Nha Trang, where it was believed the silver-backed chevrotain could be found. And Andrew Tilker – who works with Global Wildlife Conservation – formed part of the team on the animal’s trail.
The exact places where the silver-backed chevrotain specimens had been found hadn’t been recorded back in 1910. As a result, Tilker and his team had some investigating to do. So, in their search for the lost species, they spoke to local forest experts and hunters to determine whether they had spotted the animal in the area.
The location where the silver-backed chevrotain had previously been found lies within the Greater Annamites Ecoregion. The area takes its name from the Annamites Range – a mountain chain that runs down the border of Laos and Vietnam. And it provides habitats for some of the world’s rarest animals.
Amazingly, several of the rare creatures that call the Greater Annamites home have only been discovered in fairly recent times. This includes the saola – a species of wild cattle that has been nicknamed the “Asian unicorn.” It was only identified in 1992 and is believed to be one of the rarest creatures in the world.
However, due to the prevalence of poaching throughout the Greater Annamites, the ecoregion is far from a safe place of sanctuary for many creatures. That’s because hunters use wire snares to catch prey. The devices are cheap, but they are also brutal – snagging any creature that walks the forest floor without discrimination.
Poaching in Vietnam is fueled by the popularity of bushmeat throughout East Asia. But the use of wire snares has caused animals to disappear from some areas completely. This issue has been described as “empty forest syndrome,” and many animals in the Greater Annamites teeter on the brink of extinction as a result.
Given the sensitive nature of the poaching issue in Vietnam, scientists would have to tread carefully when approaching hunters in the area. So they spent time gaining their trust. And eventually, the Global Wildlife Conservation team got locals on board with their search for the silver-backed chevrotain.
An Nguyen led the expedition on behalf of Global Wildlife Conservation, and he said that locals were fully aware of the issues facing animals in the area. The expert told National Geographic, “People have become very concerned about how much wildlife has vanished in the past five to ten years. They know it’s because of overhunting and the use of snares.”
In their interviews with villages and forest rangers, Nguyen and his team pieced together potential clues to locate the silver-backed chevrotain. Some locals spoke about seeing grey chevrotains, which seemed to match the description of the lost species. So, there appeared to be hope that the animal was not yet extinct.
With the help of locals, the Global Wildlife Conservation team identified parts of the forest where there had been recent suspected silver-backed chevrotain sightings. In these areas, camera traps were established with the hope that they could collect evidence of the elusive animal’s existence.
In total, scientists set up three camera traps in the low-lying forests. For five months, the devices were poised to capture a sighting of the mysterious silver-backed chevrotain. And though the Global Wildlife Conservation team had no way of knowing what they would uncover, they would not be disappointed with the results.
Over the cause of the five-month period the cameras captured a total of 72 significant events, according to The Guardian. Scientists subsequently established a further 29 traps in the hopes of replicating the success of the first three. This led to another 208 independent events being recorded – much to the delight of conservationists.
The reason scientists were so pleased with the findings is because the camera traps did indeed find proof that the silver-backed chevrotain was still in existence. The first set of cameras captured 275 photos of the lost species, while the second lot recorded 1,881 images over the five-month period.
Footage that Global Wildlife Conservation obtained through its camera traps included evidence of the silver-backed chevrotain grazing on the forest floor. Judging from the data, the animals seemed to be solitary creatures and walked cautiously on their hoof tips. Meanwhile, it’s not clear how many of the animals were captured on film throughout the study.
The images captured by the Global Wildlife Conservation cameras marked the first time in 30 years that the silver-backed chevrotain had been sighted in the wild. The animal’s rediscovery was made public in 2019 through a press release posted on the Global Wildlife Conservation website. It also appeared in a scientific paper published in the Nature Ecology & Evolution journal.
In a statement given as part of the Global Wildlife Conservation press release, Nguyen revealed his reaction to finally locating the elusive animal. He said, “We had no idea what to expect. So, I was surprised and overjoyed when we checked the camera traps and saw photographs of a chevrotain with silver flanks.”
Nguyen, who was also studying for his PhD at the Leibniz Institute for Zoo and Wildlife Research in Germany, added, “For so long this species has seemingly only existed as part of our imagination. Discovering that it is, indeed, still out there, is the first step in ensuring we don’t lose it again. And we’re moving quickly now to figure out how best to protect it.”
Hoang Minh Duc is the head of the Department of Zoology at Vietnam’s Southern Institute of Ecology. And he also expressed his joy at the breakthrough. The expert said, “The rediscovery of the silver-backed chevrotain provides big hope for the conservation of biodiversity – especially threatened species – in Vietnam.”
Minh Duc added that finding the silver-backed chevrotain had inspired the conservation community to invest more efforts into the region. He explained, “This also encourages us, together with relevant and international partners, to devote time and effort to further investigation and conservation of Vietnam’s biodiversity heritage.”
After establishing that silver-backed chevrotains were still in existence, Global Wildlife Conservation aimed to find out more about the size of its population and how stable it was as a species. They also hoped to learn more about the distribution of the animal, and determine what threats it faced.
In order to gather more data on the silver-backed chevrotain, a team from Global Wildlife Conservation set out on the first comprehensive survey on the animals. As part of their study, the experts established camera traps in two more areas. The information gleaned from this endeavor will then be used to establish how they can help sustain the animal’s existence into the future.
Barney Long is the senior director of species conservation at Global Wildlife Conservation. And in the statement posted to the organization’s website, he expressed his joy at the rediscovery of the silver-backed chevrotain. However, Long warned that there was still work to be done if the animal was to be saved from extinction.
Long said, “It is an amazing feat to go from complete lack of knowledge of the wildlife of the Greater Annamites 25 years ago, to now having this question mark of the silver-backed chevrotain resolved. But the work is only beginning with the rediscovery and initial protection measures that have been put in place. Now we need to identify not just a few individuals on camera traps, but one or two sites with sizable populations so that we can actually protect and restore the species.”
Andrew Tilker agreed that more was needed to be done in order to protect the animal. In the report published in Nature Ecology and Evolution he said, “Stopping snaring will not only protect the silver-backed chevrotain, but also numerous other species, including several mammals and birds that are only found in the Greater Annamites ecoregion and are threatened with extinction.”
Given the success the Global Wildlife Conservation team had in locating the silver-backed chevrotain, Tilker was hopeful that other elusive animals would eventually be found. He said, “A key aspect to future surveys for lost species will be to work with local communities. Incorporating this local ecological knowledge was critical for our work, and this strategy could prove successful for other species in other parts of the world.”