The National Green Tribunal has sought a response from the Centre on two highly-invasive and alien fish species being used as biological agents for controlling mosquitoes. The tribunal was hearing a plea about two fish species -- Gambusia Affinis (Mosquitofish) and Poecilia Reticulata (Guppy) -- being released in water bodies to control mosquitoes in various states. The states which stored and released Mosquitofish were Assam, Arunachal Pradesh, Gujarat, Karnataka, Maharashtra, Rajasthan, Tamil Nadu, Uttar Pradesh, Odisha, Punjab and Andhra Pradesh, while Guppy species had been released in Maharashtra, Karnataka, Punjab and Odisha, the plea said. It said the National Biodiversity Authority declared these two fish species as "invasive and alien" as they adversely impacted the local aquatic ecosystems by causing food scarcity for the indigenous fish species. It also referred to the ban imposed on Mosquitofish by countries such as Australia and New Zealand. The plea referred to a rep