AVIFAUNAL DISTRIBUTION IN THE RATMALE TANK IN AMBAGASWEWA TANK CASCADE, SRI LANKA

Abstract

AVIFAUNAL DISTRIBUTION IN THE RATMALE TANK IN AMBAGASWEWA TANK CASCADE, SRI LANKA K.A.I.A. Kodithuwakku1#, L.A.N. Deshan1, K.G.S. Chathurangani2, S. Wickramasinghe1, W.C.P. Egodawatta2, and R.H.G.R. Wathsala2* 1Faculty of Applied Sciences, Rajarata University of Sri Lanka, Mihintale, Anuradhapura, Sri Lanka 2Faculty of Agriculture, Rajarata University of Sri Lanka, Puliyankulama, Anuradhapura, Sri Lanka *Correspondence E-mail: wathsala@agri.rjt.ac.lk, Phone: +94701747491 #Presenting Author Abstract: Ratmale tank is a seasonal tank located in the middle part of Amba- gaswewa cascade system, Anuradhapura district, Sri Lanka. The faunal diversity and their abundance in this tank were investigated. This work also highlights the threats to bird conservation in Ratmale tank. The point count method and opportunistic ob- servation were used to collect data both day and night, during the dry spell in year 2023. The data were collected from four zones, dam of the tank and slope (Z1), adja- cent dry mixed evergreen forest patch (Z2), aquatic zone (Z3), and inundated area (Z4). We identified 62 bird species belonging to 40 families including aquatic, semi- aquatic, and terrestrial birds. Among the observed 34 terrestrial birds, Gallus lafeyetii and Treron pompadora are listed as endemic species. The site contains Nettapus cor- omandelianus listed as nationally vulnerable and Merops philippinus listed as nation- ally critically endangered. Moreover, observed Haliaeetus ichthyaetus, Threskiornis melanocephalus, Anthracoceros coronatus, Limosa lapponica, and Anhinga melano- gaster have been listed as globally near threatened. The presence of Ciconia episco- pus listed as globally vulnerable reflects prime conservation attention. Pavo cristatus (23%) and Acridotheres tristis (18%) were observed as the most abundant species in Z1 zone. In Z2 zone, Psittacula krameri is the most abundant species while Micro- carbo niger was the most abundant species in Z3 (44 %). Porphyrio poliocephalus is the most abundant species (65%) in Z4 zone. Grazing to both bird number and abun- dance in the tank and its surroundings. Grazing by cattle and frequent visits of herder by motorbikes during day and night were more detrimental Thus developing a site- specific conservation plan is vital to protect the status of bird species in the tank land- scape