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Item Morphological correlates with diet of fish assemblages in brush park fisheries of tropical estuaries(Springer Netherlands., 2017) Gammanpila, M.; Amarasingha, U.S.; Wijeyaratne, M.J.S.Brush park fishery in Negombo estuary, Sri Lanka is a traditional fishing practice which relies on fishes attracted to artificial woody fish aggregation devices. This study investigates whether constituent species in these brush parks exhibit morphological variations in relation to their dietary habits. Fishes caught in brush parks were sampled from April 2014 to April 2016 covering rainy, intermediate and dry seasons. There were 817 specimens of 46 species belonging to 24 families. From each specimen, 17 morphological attributes were determined and diet composition of each species was analyzed in terms of relative biovolume. Trophic index of each species estimated from the proportions of dietary items and their possible trophic level in the community was significantly related to two body proportions (Maximum body height/Maximum body width and Total length/ Maximum body height) which described shape of fish. Principal component analysis of morphometric attributes and dietary habits indicated that the species in the higher trophic levels are characterized by slender, long-body shapes and those occupy lower trophic levels are predominantly laterally compressed with deep body shapes. As such, structure of coexisting species in brush parks of Negombo estuary is predominantly along the trophic dimension and is related to morphological traits of constituent species. The predictive power of ecomorphological correlates with diets of fish species other than mugilids which are attracted to brush parks, can therefore be considered as a useful tool for conducting rapid ecological assessment.Item Change detection in the channel segment of Negombo Estuary, Sri Lanka using time series satellite data and its possible impacts on estuarine productivity(The Asian Fisheries Society, 2011) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.Item Prosperity Challenge is in Your Hands(South Eastern University of Sri Lanka, 2017) Wijeyaratne, M.J.S.Item Monitoring eutrophication trends in Bolgoda North Lake, Sri Lanka by Satellite Remote Sensing(Central Fisheries Research Institute (CFRI) Trabzon, Turkey in cooperation with Japan International Cooperation Agency (JICA), Japan, 2016) Dahanayaka, D.D.G.L.; Perera, B.D.C.; Wijeyaratne, M.J.S.; Tonooka, H.This study was aimed to determine the present level and past trends of eutrophication of the Bolgoda North lake, Sri Lanka using in situ Chlorophyll-a (Chl-a) measurements and remote sensing data obtained from Advanced Space-borne Thermal Emission and Reflectance Radiometer (ASTER) satellite data. From March to October 2013, Chl-a, nitrate and phosphate contents of the lake were measured once a month on the days of ASTER overpass and using standard laboratory methods. Cloud-free ASTER images of the lake for the 2000-2013 period were atmospherically corrected using Fast Line-ofsight Atmospheric Analysis of Hypercubes (FLAASH) and in-situ Chl-a data were regressed with atmospherically corrected three ASTER Visible and Near Infrared band ratios of the same date. The green/red band ratio, which had the highest coefficient of determination, was used to develop algorithm for generation of 15-m resolution Chl-a distribution maps. Results indicated that eutrophication of this lake has increased from 2008 to 2011. Heavy eutrophic conditions were noted in several regions of the lake in 2013, especially in water stagnant areas and adjacent to freshwater inlets. Unplanned urbanization and inadequate facilities for waste management have resulted in heavy eutrophication of the water body. If the present trends of waste disposal and unplanned urbanization continue, enormous environmental problems would be resulted in future.Item External Quality Assessment of Higher National Diploma Programmes Offered in Sri Lanka: An Account of Best Practices(South Eastern University of Sri Lanka, 2013) Bandara, T.H.S.S.; Wijeyaratne, M.J.S.Quality assurance activities that are carried out in the Sri Lankan university system since 2002 were introduced to the alternative higher education sector in 2010. External quality assessment reviews of Higher National Diploma (HND)programme offered in eleven Advanced Technological Institutes (ATIs) located in different regions of the country were carried out to identify the best practices, strengths and weaknesses and make suitable recommendations to improve the quality of those programmes. The aspects reviewed were curriculum design, content and review; teaching, learning and assessment methods; quality of students, their progress and achievements; use of student feedback; peer observation; skills development; and academic guidance and counseling. The objective of the present study was to determine whether there are regional differences among ATIs when best practices that are in place in different HND programmes are considered. Best practices identified by the reviewers in external quality assessment review reports of HND programmes in Accountancy, Agriculture, Business administration, English, Information Technology and Management conducted in Ampara, Dehiwala, Jaffna, Kandy, Kegalle, Kurunegala, Labuduwa and Trincomalee ATIs were analysed using Principal Component Analysis to determine whether there are regional differences among ATIs with respect to best practices that are in place in each programme. Results indicated that the good practices identified by reviewers in different HND programmes do not depend on the location of the ATI, the ethnicity of the majority community and prevalence of deterrent factors such as armed secessionist conflicts in the area. Differences in the resources available and the motivation and dedication of the staff may have contributed to the differences in the good practices that are in place in different ATIs.Item Cage culture of the snakehead Ophicephalus striatus in a peaty swamp in Sri Lanka In. Zhou, et al. (eds).(Asian Fisheries Society, Manila, Philippines, 1997) Wijeyaratne, M.J.S.Item Estimation of maximum sustainable fish yield and stocking densities of fish fingerlings in fresh water lakes and reservoirs(Stuttgart : E. Schweizerbart'sche Verlagsbuchhandlung, 1964-, 1987) Wijeyaratne, M.J.S.; Amarasinghe, U.S.Item Some aspects of ecology of endemic freshwater fishes of Sri Lanka(The World Conservation Union (IUCN), Colombo, Sri Lanka and The Government of Sri Lanka, 2006) Amarasinghe, U.S.; Shirantha, R.R.A.R.; Wijeyaratne, M.J.S.Sri Lanka supports a diverse freshwater fishes, about 48% of which are endemic. Most of these endemic freshwater fish species occur in the hill country forested streams of the wet zone. There are sophisticated interactions between fish species in a fish community and its environment for food, space and/or spawning. As evident from the biology of cyprinids in hill streams in Sri Lanka, most of the endemic freshwater fish species tend to show well-defined niche segregation and ecological adaptations. Several anthropogenic activites such as deforestation, gem mining and uncontrolled use of agrochemicals, pose significant threats to survival of many endemic freshwater fish species in Sri Lanka. Exploitation of endemic fish species from the wild for ornamental fish trade is also a major cause of decline of their populations. Further, accidental introduction of clown knife fish (Chitala ornatus) and cleaner fish (Ptrygoplichthys multiradiatus), which poses threats to diversity of freshwater fishes in Sri Lanka, is an indirect adverse effect of ornamental fish trade. Although some introductions of exotic fish species such as African cichlids, most notably Oreochromis mossambicus and O. niloticus, have socio-economic benefits, effective strategies should be implemented to control transfer and introduction of aquatic organisms.Item Lavivorous Potential of Fish Species Found in River Bed Pools Below the Major Dams in Sri Lanka(Vector-Borne Diseases,Surveillance,Prevention, 2006) Wijeyaratne, M.J.S.; Kusumawathie, P.H.D.; Wickremasinghe, A.R.; karunaweera, N.D.