My research in fisheries focuses on inland capture and aquaculture-based fisheries, community-based fisheries management, indigenous knowledge in fisher communities, fisheries co-management, trophic evaluation in fish communities of reservoirs, streams and estuaries, and conservation of aquatic biodiversity. I teach aquatic ecology, environmental conservation and management, fish population dynamics and stock assessment, management of capture fisheries and aquaculture-based fisheries, at undergraduate and postgraduate levels. So far, I have trained thirty four postgraduate students (07 Ph.D. degrees, 13 M.Phil. degrees and 14 M.Sc. degrees). At present, nine postgraduate students carry out research under my supervision. I have been awarded a Doctor of Science (D.Sc.), by the Bangor University in North Wales, UK in July 2010, for my life-long scientific contribution to fisheries biology and development of inland fisheries in Sri Lanka. I was also the winner of the Excellence Award of the Committee of Vice Chancellors and Directors (CVCD) in 2008 and General Research Committee Award of Sri Lanka Association for Advancement of Science in 2009, for my lifetime achievement as the most outstanding scientist Sri Lanka in biological sciences.

Management of reservoir fisheries; Trophic dynamics in lake and reservoir ecosystems in tropical Asian countries; Culture-based fisheries in small reservoirs; Stream ecology; Life history patterns of fish communities; Community-based fisheries management in coastal fisheries, lagoons and estuaries; Fisheries co-management in reservoirs and coastal estuaries; Capturing indigenous knowledge for fisheries co-management; Flotsam associated fisheries in the Indian ocean; Beach seine fisheries in Sri Lanka; Valuation of multiple uses of irrigation reservoir resources; Investigation of the effect of hydrological regimes in irrigation reservoirs on fish yields and life history patterns of cichlid fish species; Investigation of nesting behaviour of exotic cichlid species in irrigation reservoirs.