IMPORTANCE OF GRASSLAND ECOSYSTEM FOR CONSERVATION OF DRY ZONE AVIFAUNA
I.A.I. Sandunika Ileperumarachchi
Rajarata University Of Sri Lanka
Sri Lanka’s avifauna is one of the richest in the whole of Asia. The availability of different kinds of ecosystems throughout the country contributes to high avifaunal diversity and among them grasslands are significant. This study was conducted to emphasize the importance of grassland ecosystem adjacent to Mihintale sanctuary which located in the dry zone, in the aspect of habitat utilization by avifauna and applying it as tool for their conservation.
The study was started from November 2011 to the end of February 2012. Data was recorded using 500m length line transect and the opportunistic observation in the morning and evening. Birds were counted along the fixed width of 25 m on either side belt transect using two pair of binoculars (Bushnell 10x50) and identifications were made with the aid of field guides. Difference of the diurnal variation was analyzed using one way ANOVA.
The grassland was occupied a total of 81 species belonging to 35 families. There were 2 endemic, 69 breeding residents, 14 winter visitors and 3 proposed endemic species. 67 were common while 3 species were recorded as rare. The majority was insectivores (41.96%) and lowest was nectarivores (3.57%). It provides food, nesting materials and roosting site for 16 and nesting site for 13 bird species. There was no significant diurnal variation in diversity (P = 0.25).
The grassland adjacent to the Mihinthale sanctuary holds value being an ecologically important ecosystem that provision habitats for considerable number of bird species. Availability of food, presence of different type of habitats , provision of nesting materials, and vegetation structure attract the birds whose requirements are fulfilled with the conditions in the grassland and through that the grassland contribute to the survival of dry zone avifauna.