ULSAN — A pair of Siberian flying squirrels, a designated Natural Monument and a Class II endangered species in South Korea, has been found for the first time along a walking trail by the Taehwa River in Ulsan. It marks the first confirmed nest and habitat in a downtown riverside trail frequented by residents, rather than in outlying forests such as Seoknam Temple or Mount Cheonma.
Ulsan said on the 6th that it had confirmed two flying squirrels living in a tree nest along a riverside walking trail in the middle reaches of the Taehwa River.
The observation began on the afternoon of Sept. 9, when Lee Chan-sook, a nature interpreter, spotted and photographed one flying squirrel that had woken and was looking out from a woodpecker nest near the trail. Yoon Ki-deuk, a photographer and citizen scientist, then visited the site around dusk on the 17th and 23rd and recorded video of two animals moving in and out of the nest.
Han Sang-hoon, a researcher at the Korean Peninsula Wildlife Institute who analyzed the material, said the sighting of two animals together is notable because flying squirrels normally live alone. "They are presumed to be a male and a female ahead of breeding," Han said. "Given that the species breeds once or twice a year, it appears they have not yet given birth, so continued observation is needed."
Measuring about 15 to 20 centimeters in body length, the Siberian flying squirrel is a nocturnal rodent that glides between trees using a membrane of skin stretched between its front and hind limbs. It was designated a Natural Monument in 1982 and is protected as a Class II endangered species by the Ministry of Climate, Energy and Environment. In Ulsan, the species had previously been confirmed only in deep forest areas, including the grounds of Seoknam Temple and Baenae Village in Ulju County and a cypress grove on Mount Cheonma in the Buk district.
Ulsan said it decided not to disclose the exact location to protect the habitat and allow the animals to breed undisturbed.
"The presence of flying squirrels on the Taehwa River trail, a downtown recreation area, is an indicator that the river's ecosystem has been restored to health," an Ulsan official said. "We ask that people refrain from excessive noise when using the trail so these nocturnal animals can rest."
