Koshi Tappu’s Vital Role in the Central Asian Flyway
The role of Key Biodiversity Areas for the Pallas's Fish-eagle and Bar-headed Goose across the Central Asian Flyway.
Header Image: Pallas’s Fish-eagle © Rakesh Dhareshwar.
Across the globe, billions of birds traverse superhighways in the sky known as flyways, connecting distant cultures, landscapes, and ecosystems. Among the main flyways on Earth is the Central Asian Flyway. This flyway is key for more than 600 bird species, connecting the breeding grounds in Central Asia, Mongolia, and Siberia to the wintering grounds in South Asia, the Middle East, and the islands of the Indian Ocean.
One of the priority sites for the Central Asian Flyway, identified by BirdLife International, is the Koshi Tappu Wildlife Reserve (KTWR) in Nepal. Recognised as a Key Biodiversity Area (KBA) and an Important Bird and Biodiversity Area (IBA), this site serves as a life-saving sanctuary for species navigating the skies.
Due to its importance, Koshi Tappu was designated as an IBA in 2005, and later qualified as a legacy KBA because it is one of the most species-rich sites in the entire Central Asian Flyway, supporting a staggering 535 bird species. Koshi Tappu’s strategic importance is defined by its geography along the southern slopes of the Himalayas. For migratory birds, these mountains are a massive natural barrier. In this scenario, Koshi Tappu acts as a vital refuelling station where birds rest and recuperate before or after their high-altitude crossings.
Among the amazing bird species that traverse this flyway is the Bar-headed Goose. These birds perform one of nature’s most incredible feats, flying at high altitudes and crossing the Himalayas multiple times during their lives. They possess unique physical adaptations to breathe in oxygen-thin air and strategically time their flights for when the air is cooler and denser. For these geese and the various species that use the Central Asian Flyway, the wetlands of Koshi Tappu, which cover over 22% of the reserve’s core, are essential for their survival.
Another incredible traveller that depends on Koshi Tappu as a junction and wintering ground is the Pallas’s Fish-eagle. This high-altitude traveller, which reaches altitudes exceeding 6,000, breeds in northern India, Bangladesh, Myanmar, and Bhutan, dispersing north of the Himalayas to Kazakhstan, Russia and Mongolia in its non-breeding season. The Pallas’s Fish-eagle is listed as Endangered on the IUCN Red List and is threatened by habitat loss, degradation and disturbance.
Beyond their connection to Koshi Tappu, both the Bar-headed Goose and the Pallas’s Fish-eagle are deeply intertwined with other Key Biodiversity Areas along the Central Asian Flyway. Sites such as the Kaziranga National Park in India, a biodiversity-rich World Heritage site, and Ogii Lake in Mongolia, categorised as a Ramsar Site, are also essential for their migration journeys and overall persistence.
Conservation along the flyway
To reverse the trend and ensure migratory birds continue thriving in all the countries they depend on, their protection requires shared responsibility across borders. At Koshi Tappu, conservation is a layered effort addressing local and regional threats.
The Koshi Tappu Wildlife Reserve is managed by the Nepal Government’s Department of National Parks and Wildlife Conservation, and its buffer zones are managed through Buffer Zone Users Committee, focusing on biodiversity protection, wetland conservation, and community livelihoods. Bird Conservation Nepal (BCN), BirdLife’s Partner in Nepal, supports these efforts. BCN works with the government and local communities to improve habitat for migratory birds. Initiatives include awareness raising, capacity enhancement, policy support such as conservation action plans, utilising invasive species for improving livelihoods of local communities, and promoting sustainable fisheries to reduce illegal pressure on the reserve’s core resources. BirdLife is currently supporting a BCN project to assess the ecosystem services provided by the park, and to identify the livelihood interventions needed for marginalised local communities.
BirdLife also supports other conservation efforts across the flyway, utilising a unique local-to-global approach to deliver high-impact protection for migratory species. In cooperation with the CMS Secretariat, BirdLife has produced a comprehensive Central Asian Flyway – Situation Analysis, providing a factual baseline of the conservation status and threats facing birds in the region. Building on this analysis, the partnership has established a dedicated strategy for the Central Asian Flyway, which integrates work across multiple regions into a single framework to address challenges at a flyway scale. A critical component of this programme is the identification of 32 priority sites selected for immediate conservation action based on their importance to migratory birds and the level of threat they face. The Koshi Tappu Wildlife Reserve is distinguished as one of these 32 Central Asian Flyway priority sites, marking it as a vital focal point for BirdLife’s regional conservation interventions.
To ensure migratory birds thrive and have safe places to rest, refuel and shelter, conserving the key sites they depend on is essential. By securing critical nodes like Koshi Tappu, we can ensure that the highways in the sky remain open for the next generation of high-flying travellers.
