Population study of waterbirds and the assessment of the suitability of Khuan Khi Sian, Thale Noi Non-hunting as a Ramsar site

Abstract

This study investigated the population density and the breeding period of waterbirds in Melaleuca swamp forest at Khuan Khi Sian, Thale Noi Non-hunting Area from April 1998 to March 1999. The number of these waterbirds was counted monthly and their breeding activities were also observed. A total of 46 species of birds was recorded, the species of which could be classified into 30 species of residents, 8 species of migrants and 8 species of partial migrants. Of 46 species, 18 species were waterbirds, but only 5 species used Melaleuca swamp forest as a breeding site, i.e. Phalacrocorax niger, Ardea purpured, Bubulcus ibis, Egretta garzetta and Nycticorax nycticorax. This breeding colony also served as a roosting site for Threskiornis melanocephalus, a rare species of Thailand. The population density of waterbirds in the breeding colony fluctuated greatly throughout the year. The peak of waterbirds was in May when the number ofindividuals ranged from 13,867-20,217. The breeding activities also peaked in this month and in June. Of all the waterbirds, only Phalacrocorax niger and Ardea purpurea used this breeding colony throughout the year. It was found that Bubulcus ibis, Nycticorax nycticorax and Threskiornis melanocephalus showed the correlation between the number of individuals and environmental factors. From this study it might be concluded that Khuan Khi Sian is suitable to be a Ramsar site because it meets the criteria 1-6 of the criteria for identifying wetlands of international importance