Diversity of Dragonfly Species in the Hakkinda Islands of Mahaweli River in the Gatabe Area

Abstract

Hakkinda Islands surrounded by the Mahaweli River, close to the Kandy-Gatambe area is a bio-geographical hotspot in Sri Lanka. However, biogeographical importance of these islands has been overlooked during the last few decades as a result of development projects and wide-ranging human activities. Considering this fact, the President of Sri Lanka declared the Waratenna-Hakkinda geographical region as a conserved/ protected environmental area. According to the rudimentary survey, this protected area can be identified a special habitat to dragonfly species, which biologically comes under the ‘insect’ category (order- Odonata & infraorder- Anisoptera). Since the existing literature written on diversity of dragonfly species shows an inadequacy, the main objective of this research is to explore and examine the variation of this particular species inhabited to the research area. This research is guided by Quantitative-Deductive research methodology. Under this methodology, line transects, and quadrate sampling methods have been used for primary data collection. According to the research findings, a total number of 16 dragonfly species belonged to 08 families were identified and both riverine forest and river islands have rich diversity compared with home gardens in the area. Among the available species, 37.5% are identified to be endemic to the country. Three species, namely, Oriental Green Wing (Neurobasis chinensis), Black-tipped damsel (Vestalis apicalis) and Sri Lanka Ultima gem (Libellago finalis) are identified to be endangered/ vulnerable species. This research concludes that theough there are a high diversity of dragonfly species in the river islands and riverine forest areas, human activities and their irresponsible behaviour have directly and indirectly influenced negatively on dragonfly habitats and their breeding colonies. The research, thus, identified an immediate requirement for a regulatory mechanism to protect this biologically important breeding colony of dragonfly species and their habitats to protect their diversity.