Rapid impact assessment of extremely severe cyclonic storm Fani on morpho-dynamics & ecology of Chilika Lake, Odisha, India

Abstract

This article evaluates the impacts of ‘Fani’, a category four cyclone on the shoreline and ecology of the largest brackish water lagoon of Asia, Chilika, on the East Coast of India. The cyclone forced open two New Tidal Inlets (NTI) along the northern shore of the lagoon’s outer channel leading to erosion of the embankments and spits. The average rate of change due to cyclonic storm ‘Fani’ was – 6.12 m while 66.03% of the total transects registered symbol of erosion along the shoreline of Chilika lagoon. Post Fani the information made available on its impact on Chilika was minimal which made us to look into published news articles, online news channels,past published scientific literature to corroborate the likely impact of such erosion and new tidal inlets on the lake ecosystem. Experts differed on their opinions on how the plankton, fish, seagrass and critically endangered Irrawaddy Dolphin would respond to the salinity changes in the lake aftermath of the cyclone. Some of the impacts of ‘Fani’ on the lake shoreline and ecosystem were imminent, such as the opening of tidal inlets and spot death of three Irrawaddy dolphins; whereas, long-term impacts such as changes in the biomass and composition of plankton communities, fish and bird population in the lake are primarily unknown and warrants further detailed investigation. Nevertheless, the study asserts that cyclone driven shoreline damage can impact lagoon ecosystem by bringing in a rapid change in the salinity field