The Black-bellied Tern (Sterna acuticauda) is a water bird species generally found near large rivers, and shallow wetlands for nesting and feeding. Their breeding takes place from February to April, nesting usually in a flat sandy location near a river or lake. Once widespread across south and Southeast Asia, its population is now fragmented across Nepal, India, Myanmar, Pakistan and Bangladesh, with an estimated global population of only 800-1,600 mature individuals, indicating a significant population decline despite its once extensive distribution range. It is listed as “Endangered” on the IUCN Red List due to its rapid population decline over the past 27 years. The Black-bellied Tern is more susceptible to extinction than other terns, due to various threats like industrial pollution, invasive species outbreaks, over-harvesting of wetland products, nest trampling, egg collection, and human disturbance. This tern species requires large sand spits and mudflats for nesting and resting. Additionally, habitat loss due to sand mining and flooding caused by shifting water levels further increases their vulnerability.

The Black-bellied Tern populations in Nepal are very small, likely hosting no more than 20 birds. The breeding population in Chitwan National Park has completely disappeared, primarily due to increased disturbance and over-harvesting of wetland products. In Nepal, wetland birds face the most critical threats compared to those in other habitats, with the most noticeable species declines occurring in Koshi Tappu, a premier wetland site. The tern numbers in the Koshi have plummeted from over 60 individuals to fewer than 10 in 2010.

Despite this decline, there is a lack of species-specific research and conservation actions for the terns in Nepal. Thus, this project aims to address the research gap by conducting field research to determine the population status, distribution, and conservation threat of the Black-bellied Tern within the potential habitats of Koshi. This information will be valuable to initiate conservation interventions targeting the locals to aware them and contribute to the conservation of Black-bellied Terns in Koshi.

The objectives of this project are;

The project is supported by The Waterbird Society and Idea Wild