Coral survey and monitoring

  • The comprehensive baseline data on coral reefs in Gulf of Mannar has been collected. The collected data from Gulf of Mannar was also published in the form of scientific book titled “Coral reefs of the Gulf of Mannar, Southeastern India – Distribution, Diversity and Status”, which contains updated comprehensive information on the ecological, faunal and floral status and forms a bench mark for any future monitoring.
  • The survey revealed that the overall live coral cover was 36.98% during 2003-2005 and an approximately 32 km2 reef areas have been degraded.
  • Further regular surveys are being conducted and the live coral cover increased to 42.85% in 2009 due to a complete halt to coral mining in 2005 and reduction in the disturbance to reef areas, in combination with successful reproduction and high recruitment.
  • Coral mortality due to elevated sea surface temperature and bleaching reduced live coral cover to 33.2% in 2010. Steady recovery in 2011 and 2012 increased the live coral cover to 37.8% in 2012.
  • Though significant increase in coral cover is noticed, efforts have to be taken to manage the reefs from compounded threats of direct local stress and climate change.
  • In Palk Bay, the overall live coral cover was 30.78% in 2007 and 28.24% in 2013. Destructive fishing practices, degradation of water quality and increased prevalence of diseases are main responsible factors for coral loss in Palk Bay.