The elusive animal, known for its speed and stealth, was captured on camera on June 26, peeking out from a crevice in Jirisan National Park. (Image courtesy of Korea National Park Service)
SEOUL, July 11 (Korea Bizwire) — For the first time in eight years, South Korea’s National Park Service has confirmed a sighting of the Musan least weasel, one of the world’s smallest carnivorous mammals and a critically endangered species.
The elusive animal, known for its speed and stealth, was captured on camera on June 26, peeking out from a crevice in Jirisan National Park, the Korea National Park Service (KNPS) announced Wednesday.
Named after its first recorded location in Musan County, North Hamgyong Province in 1927, and the Korean word “soe”, meaning small, the Musan least weasel measures just 15 to 18 centimeters in body length and weighs between 50 and 150 grams — similar in size to a common rodent. Despite its tiny frame, it is a formidable predator, feeding primarily on rodents and small vertebrates.
Known for consuming up to 2,000 to 3,000 mice annually, the species has earned the nickname “mouse-eating mouse” in North Korea. It is also an adept burrower, often taking over rodent tunnels rather than digging its own.
(Image courtesy of Yonhap)
While the species was first spotted in South Korea in 1974 during construction in Seoul, it has since been presumed to inhabit mountainous areas nationwide, with confirmed sightings in ten national parks, including Jirisan and Seoraksan. Still, its precise population and habitat range remain unknown.
Sightings are exceptionally rare due to the animal’s hyperactive nature and low population. The last confirmed observation in a national park was in 2017, also in Jirisan.
The Musan least weasel’s small size makes it vulnerable to predators like owls and snakes, and its average lifespan is less than a year. Environmental changes, including climate-driven habitat disruption and declining prey populations, have placed the species at high risk of extinction.
Designated as a Grade I endangered species by the Ministry of Environment, the Musan least weasel is also prioritized for restoration under South Korea’s comprehensive wildlife conservation plan.
Officials say the recent sighting offers a rare and hopeful opportunity to further study and protect one of Korea’s most elusive and ecologically significant mammals.
Lina Jang (linajang@koreabizwire.com)
