The province announced the establishment of the Kim Bang Delacour's Langur Species and Habitat Conservation Area at a ceremony in Tam Chuc Ward on November 3.
Under the provincial People's Committee's decision, the special-use forest reserve covers nearly 3,200 hectares across Ly Thuong Kiet, Tam Chuc and Nguyen Uy wards.
Delacour's langur (Trachypithecus delacouri), also known as the white-rumped langur, is endemic to Vietnam and classified as critically endangered on both the Vietnamese Red Data Book and the International Union for Conservation of Nature (IUCN) Red List.
It is also listed among the world's 25 most endangered primates.
In the 1990s, the species was estimated to have around 300 individuals across 16 isolated populations. Today, only five wild populations remain, with approximately 540 individuals.
Ninh Binh is home to nearly 470 langurs, accounting for around 90 per cent of the estimated population.
Scientists have confirmed at least 116 individuals in Kim Bang's limestone forests, making it the world's second-largest population after Van Long.
The new reserve comprises three zones: more than 1,807 hectares under strict protection, nearly 1,360 hectares designated for ecological restoration and approximately 16 hectares for administrative and service activities.
The zoning aims to protect natural habitats, restore forests, expand the langurs' living areas and support scientific research.
Speaking at the ceremony, Ninh Binh Vice Chairman Tran Anh Dung highlighted the ecological importance of the Kim Bang population and said the reserve would support national forestry planning and sustainable development.
He instructed the Department of Agriculture and Environment to coordinate forest management, apply technology to monitor langurs and forest conditions, and strengthen conservation efforts.
Local authorities were also asked to increase patrols, address violations and link conservation with livelihoods in surrounding communities.
Construction and mineral extraction near the reserve must be closely controlled to prevent habitat fragmentation and degradation.
The Kim Bang reserve also forms part of the Van Long-Kim Bang-Tam Chuc heritage landscape, for which a potential UNESCO World Heritage nomination dossier is being studied.