Occurrence of opportunistic invasive macroalgal genus Caulerpa and Halimeda opuntia in coral reefs of Gulf of Mannar

Abstract

nvestigations on indigenous and non-indigenous invasive flora and fauna of a certain geographical area are always important to assess their impact on native biodiversity and control their spread by making conservation strategies to protect biodiversity. In this study, we have encountered overwhelming growth of six seaweed species, Caulerpa racemosa, C. serrulata, C. sertularioides, C. taxifolia, C. peltata, and Halimeda opuntia on the reef flat. These algal covers on reef area appear to compete with coral polyps and restrict their settlement and resilience. Our concern on invasive species distribution in Gulf of Mannar revealed these overgrowing invasive species, which can become potential threats to coral reefs, benthic diversity, and reef assemblage. These observations will help us to develop multidisciplinary management approaches related to the expansion, mitigation, and control of these opportunistic invasive species. Further seasonal monitoring on these algal species is under process to investigate their spatial shift patterns on various coral forms.