Otter species can be used as flagship to promote the protection of aquatic environments in regions where they are known or regularly seen. In a previous study on the perceptions of local communities about the Neotropical otter (Lontra longicaudis) in Central-South São Paulo State, Brazil, we identified knowledge gaps and population groups with potential for conflict with the species. We also assessed the species local distribution and found that habitat quality was deteriorating, due to aquatic contamination by urban waste and antibiotics and destruction of the riparian vegetation. To tackle this situation, with financial support from the National Geographic Society, we designed and implemented an awareness campaign having the Neotropical otter as a flagship species (“Projeto Neolontra“). The project goals were to: i) raise awareness on aquatic species and habitats valuing the previews information given by the population; ii) prevent the intensification of human-otter conflicts; and, additionally, iii) complete the assessment of otter distribution in the region, building on local knowledge and field campaigns. For that we conducted 27 talks to 1337 attendees between August and October 2017 and produced awareness materials (posters, t-shirts, handouts), informally delivering science-based information to local populations. With this project we were able to link societal challenges, biodiversity conservation principles, and education actions, involving local partners and institutions, contributing to empower their role within the community and influencing decision makers on issues such as water use, riparian habitats preservation, urban waste effects, and medications disposal needs