The fish, including critically endangered Mekong giant catfish and giant barb, and endangered striped river catfish, were released into a series of fish sanctuaries and community conservation areas that protect crucial fish nursery habitat in Tonle Sap Lake, the world’s most productive inland fishery. Long-term survival of the Mekong’s threatened fish species will also depend on protection of migration corridors and upstream spawning grounds, and on maintenance of free-flowing and connected watercourses, say experts.