The silver-backed chevrotain (Tragulus versicolor), also called the mouse deer or cheo cheo by the locals, was spotted in southern Vietnam after nearly three decades, instantly taking over hearts on the internet.
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The rediscovery of the silver-backed chevrotain (Tragulus versicolor) brought with it much global excitement and hope of further conservation of this unique and shy forest dweller. This elusive mammal was lost to science for almost three decades, but its presence was confirmed in the Greater Annamites region of Vietnam through extensive camera trappings.
A 2019 study published in Nature Ecology & Evolution revealed the first scientific photographic evidence of the species in over three decades. This breakthrough not only confirmed that the species was still alive but also revealed new clues about its habitat use and behavior.
The Silver-Backed Chevrotain
Chevrotains are commonly referred to as mouse-deer, and upon first glance, it’s simple to understand why. They resemble pocket-sized deer, barely larger than a rabbit. But other than the moniker, they’re nothing like the deer family whatsoever. They’re members of their own ancient family of hoofed mammals referred to as Tragulidae, inside an infraorder called Tragulina, meaning “little goat.” They’re the smallest hoofed creatures on the planet and also one of the oldest.
They split off from all other ruminants around 50 million years ago, carrying with them unusual traits: four dainty toes instead of two, tiny fang-like tusks and in some species, the ability to slip underwater and stay submerged for minutes at a time.
Some scientists believe they look like the sort of ancient mammals that went on to develop into hippos and whales. Most chevrotains are found in Asia, with only one far-off cousin, the water chevrotain, in Central Africa.
Amid this ancient family, the silver-backed chevrotain is especially remarkable. Found only in the lowland forests of southern Vietnam, it is both rare and deeply significant to the country’s natural heritage. About the size of a rabbit, it has a shimmering silver-gray back, a warm reddish-brown head and two delicate tusks that give it a secretive, almost mythical look. It moves alone during the day feeding on fallen fruits, young leaves and tender shoots while staying hidden from predators — and from people.
Recent genetic research has revealed just how singular this species really is. A 2024 study published in Mammalia showed that the silver-backed chevrotain forms its own distinct evolutionary lineage, sitting as a sister branch to all other species in the genus Tragulus. Because it has not been secured across most of its range, the study emphasized that the small population inside Nui Chua National Park — the only known group living within a protected area — should be treated as a top conservation priority.
Disappearance And Rediscovery Of The Silver-Backed Chevrotain
The species was first described in 1910 by British zoologist Oldfield Thomas. After that, it was recorded only once more, in 1990, before being rediscovered in 2019.
In 2019, a team led by Vietnamese biologist An Nguyen, working with Global Wildlife Conservation and the Southern Institute of Ecology, captured nearly 2,000 images of the animal using camera traps — the first scientific confirmation of its continued existence in modern times.
The rediscovery was not a case of luck. Prior to installing cameras, Nguyen’s researchers spent weeks trekking through villages and towns on the edges of Vietnam’s Greater Annamites forests. Locals refer to the animal as “cheo cheo” and said they spotted a little deer-like animal with a silver sheen, providing researchers with good leads on where to look.
Guided by this local knowledge, the team placed motion-triggered cameras deep inside the forest. Months later, when they collected the devices, the first photos revealed a tiny silver-flanked creature picking its way across the forest floor. Encouraged, they expanded their effort with dozens more cameras, documenting over 200 appearances.
For Nguyen, the breakthrough showed how pairing local ecological knowledge with modern technology can bring a species back from the edge of obscurity — and into the global spotlight.
Excitement Over The Rediscovery And Viral Fame Of Silver-Backed Chevrotain
When the silver-backed chevrotain’s rediscovery was made in November 2019, the news was an instant global sensation world-wide. Conservation organizations posted the camera trap images, and before long, major publications were featuring headlines about the “lost” mouse-deer that had returned after almost 30 years.
Social media helped turn the tiny creature into an unlikely star. A short clip of the rabbit-sized chevrotain stepping shyly into a camera frame went viral, drawing millions of views on Instagram. Comment sections filled with awe and disbelief as people marveled that something so fascinating could have stayed hidden for so long.
For conservationists, the sudden global buzz was more than just heartwarming — it was a rare moment when public attention centered on a small, overlooked species.
Years Later, Cheo Cheo Is Still Facing Conservation Hurdles
Although its rediscovery was greeted with much encouragement, the silver-backed chevrotain’s future is far from certain. It exists only in Vietnam, and years of wild meat hunting — a long-standing, culturally ingrained practice — have put what remains under severe pressure. Habitat destruction due to farming and urbanization still encroaches on the forests it relies on, and since so few have been seen, researchers still have no idea how many are left.
One major hurdle is that the species has not yet been listed as endangered by the International Union for Conservation of Nature (IUCN) due to a lack of data. This makes it harder to secure funding, legal protections or strong conservation policies.
A 2024 review in Pacific Conservation Biology stressed that traditional top-down measures alone are unlikely to work. Instead, it calls for efforts that involve local communities and build empathy for the animal, especially among children.
The researchers argue that using modern tools — from social media and crowdfunding to AI-driven citizen science — could help spark public interest and create a sense of shared responsibility for its survival.
They even suggest shifting how the species is talked about. Calling it “cheo cheo,” its Vietnamese name, could create familiarity and pride, helping local people see it as part of their shared natural heritage — and building the cultural support it may need to survive.
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