Coastal and marine ecosystems are under increasing pressures globally. Support for those ecosystems is often strongest when initiatives focus on “iconic” species, those with ecological importance and cultural, social, or economic value. The Coorong and Murray Mouth region is a Ramsar Wetland of International Importance and a Murray–Darling Basin icon site. Despite its status, the Coorong and Murray Mouth has experienced major degradation, from river regulation, drought, high salinity, species losses, and ecosystem disruption. The region holds deep significance for the Ngarrindjeri people as part of Yarluwar-Ruwe, with strong cultural connections expressed through creation stories, culturally important species, and long-standing practices such as fishing, weaving, language, and governance. This project developed an inclusive list of iconic flora and fauna by integrating threatened status and ecological function with First Nations knowledge and broader community perspectives. Using literature reviews, community outreach, and yarning circles, our research team assessed > 200 aquatic species and used a scaling concept to identify > 30 key iconic marine and estuarine species for priority research and conservation. The iconic species list provides a pathway for conservation, research, and investment priorities, and underscores the need for stronger collaboration among researchers, managers, and First Nations communities.