Water Quality and Fishery Yield in the Batticaloa Lagoon Prior to and After Tsunami

Abstract

A large proportion of the coastal population of the Batticaloa district depends on the Batticaloa lagoon for their daily bread from time immemorial. This has been made possible due to the high degree of biological diversity in the lagoon. In this study an attempt was made the diversity of fauna with reference to fish and shell fish, diversity of flora in terms of mangroves and also records the diversity of ecological services provided by Batticaloa lagoon to humanity. Eleven sampling points were chosen randomly to collect data from the fish landing centers along the lagoon, regarding the fish catch, water quality. The fish catch statistics for fin fish and shell fish were collected for a long period but to compare the impact of Tsunami upon fisheries the data from 1993 to 1995, 2003-2004 and from 2004 to 2005 are considered in this study. The mean catch per unit effort from the Batticaloa lagoon was recorded as 2.55 kg, 2.14 kg, 2.9 kg and 1.98 kg per person per day for the period from 2004–2005, 2003–2004, 1993-1994 and 1994- 1995 respectively. Orechromis spp and Etroplus spp dominated the catches. However, during December to February shrimps EUSL Water Quality and Fishery Yield in .... 35 especially Penaeus indicus, Penaeus semisulcatus dominated the catch. The fish catch and its market value showed impacts on the economy and life style of the fishermen. The analysis reveals that the lagoon water still retains reasonable standards of water quality in many areas except in selected pockets where industries are heavily concentrated. The shocks imposed by the modern stakeholders through industrial activities are unbearable most of the time, but the system does not show any serious signs of collapse due to the free delivery of ecosystem services such as delivery of lagoon consumable products to human. The water quality of different locations was also studied where at some places the nitrate, phosphate levels were higher in Kattankuddy and Thiruperumthurai, where the untreated municipal garbage, industrial wastes are pumped. The scenario is likely to be worsening if proper environmental governance is not adopted by the stakeholders.