National Park

This dry zone sanctuary is mainly comprises with three lakes namely, Weerawila wewa, Debara wewa and Pannagamuwa wewa. Yodha wewa and Tissa wewa are another two lakes, which located little far away from above three lakes. All these lakes are act as ideal habitats for shorebirds. Since they are situated close to south coast and Bundala National Park, which is the south most destinations of the migratory birds of Sri Lanka lot of migratory birds also can be seen here. Egrets, Cormorants, Asian Openbill, White Ibis, Eurasian Spoonbill and many winter migrants can be seen here. Being the most prominent water resources in the area these tanks attracts considerable number of animals during the dry season. However the most common animal of the area is feral Buffalos.

Weerawila can be reached from South Coast on your way from Yala passing Hambantota a fascinating fishing town with a Natural harbour Location: 60 24’ 0 N and 810 12’ 0 E to 60 8’ 0 N and 810 20’ 0 E; 707426 N and 522117 E to 677955 N and 536881 E; between 5-10 km inland from the southeast coast around the town of Tissamaharama, in the Hambantota District, of the Southern Provinc.

The tank cluster lies within the southeast low country dry zone and receives 1,100 – 1,200 mm rainfall annually. Most of the rainfall occurs within March-May and October-January periods. Annual average temperature is around 270C with minimal monthly fluctuations. The southwest monsoons (May to September) bring desiccating winds, which cause severe drought conditions locally. These tanks, being part of a cascade, are hydrologically interlinked. The main canals of the KOISP scheme intersect the natural catchments of the tanks, while most water entering the tanks originate from the Lunugamvehera reservoir. Due to the predominance of paddy cropping on highly percolated soils, there is marked water shortage and as a result most tanks dry out regularly due to competition for these scarce water resources. Principal soil classes in the valley are low humic gley soils and poor to imperfectly drained alluvial soils.

Conservation

The area forms part of the old remnants (> 2000 years) of the Kingdom of Ruhuna, which includes ancient tanks and 4 dagobas that are of national archaeological significance. Most of the people in the area are poor and depend on government assistance. A large number of families raise cattle and buffaloes. Around 25 families are involved in extracting lotus flowers from the Debara Tank as a livelihood.

Scientific research and monitoring:

Studies conducted in and around the tank system include bird censuses conducted by the CBC, various fisheries programmes undertaken by universities and NARA, water quality studies undertaken by the Agricultural Experimental station, Weerawila and more recently several research activities have been undertaken by IWMI.

Flora

The seasonally inundated vegetation is dominated by trees such as Terminalia arjuna, Diospyros malabarica and Vitex leucoxylon. The catchment forests consist of timber species such as Manilkara hexandra, Dryptes sepiaria and Chloroxylon sweitenia. The native aquatic vegetation of the tanks includes Nymphaea pubescens, Utricularia spp., Ceratophyllum demersum, Polygonum spp., and Ludwigia adscendens.

Founa

The freshwater fish in the tanks are dominated by exotic species such as Oreochromis spp., Catla catla, and Labeo rohita. The aquatic reptiles in the tanks include Crocodylus palustris, Melanochelys trijuga and Lissemys punctata. The tanks are home to several large water birds (e.g. Ardea cinerea, Threskiornis melanocephalus, Anastomus oscitans, Mycteria leucocephala, Pelecanus philippensis), large flocks of waterfowl (Anas querquedula, Dendrocygna javanica) and cormorants (Phalacrocorax spp.). These tanks also function as important water sources for large mammals such as Elephas maximus.