Avifaunal Diversity of Kirala Kele: A Man - influenced Wetland Ecosystem

Abstract

Kirala Kele man-made wetland is considered as one of the most valuable conservation areas in the Matara District. Therefore, the main objective of this study is to document avifaunal diversity of the Kirala Kele wetland ecosystem by estimating the avifaunal richness, density, diversity and evenness in wetland. Avifaunal survey was done by using different sampling methods such as point count method and scan survey techniques. Shannon Index of diversity (H') and Shannon Evenness measure (E) were used to calculate diversity and evenness. In addition two separate blocks in the wetland which have different flora composition were compared against in two seasons and compared a same block within two seasons of the year. Statistical Analysis was done by one way ANOVA with fisher's pair wise comparison and MINITAB 14.103 species were recorded including, 3 endemic species. Thick forested areas had the highest bird diversity index (H'=2.099) while the lowest diversity (H'=0) was observed in the Acacia spp dominated habitat. Diversity index and evenness was significantly changed from migratory (H'=1.001 with E=0.382) to non migratory (H'=1.93 3 with E=0.795) seasons due to large segregation of migratory birds (predominantly water birds) in migratory seasons. The lowest diversity index was resulted from area with higher weed composition (H'=1.288) compared to lesser weed floral composition (H'=1.933). Overall, avifaunal diversity was quite high in the wetland, yet low in endemic and threatened species. However, as a wetland Kirala Kele ecosystem plays an important role for maintaining population of water birds.