Lumbini, Feb. 2 -- A national water bird census conducted last month from Lothar to Ghatgai along the Rapti river in Chitwan, recorded a total of 2,740 ruddy shelducks, a sharp decline from 4,107 counted in the same stretch last year.

The drop was even steeper at Jagadishpur lake in Kapilvastu, one of the country's most important wetlands, where around 2,000 fewer whistling ducks were recorded last year but only around 200 were counted this winter. Notably, these birds were found not inside the lake but in nearby farmlands, indicating a loss of suitable habitat within the wetland itself.

Nationally threatened water bird species have declined further. The cotton pygmy goose, of which 72 individuals were recorded last year in Jagadhispur,...