Recreational fisheries are notoriously hard to manage, monitor and govern. This often requires managers to think “out of the box” and disregard traditional methodologies designed to manage fisher behaviour. Social media, which is an informal technological scholastic platform for the communication and dissemination of information, has become an important platform for community organisation and engagement in pertinent issues such as conservation, and has great potential for altering the behaviour of fishers. Recreational fishers use a variety of social media platforms to engage, communicate and organise themselves for a variety of reasons, yet its potential for promoting pro-environmental behaviour has not been assessed. The aim of this study was to explore whether user-generated content on Facebook has the potential to encourage pro-environmental behaviour among recreational anglers and to discuss how fisheries managers and scientists can facilitate this process. To do this we monitored angler environmental attitudes and behaviour on a large South African Facebook group, Salt Fishing South Africa (SFSA) (∼ 60,000 members, at the time of the study) and engaged with conceptual frameworks on the use of social media to facilitate pro-environmental behaviour. We found evidence for pro-environmental reform on the SFSA Facebook group, with significantly more catch and release posts, more pro-environmental comments, and improved fish handling practices over time, despite no intervention from fishery scientists or managers. These improvements were most likely attributed to a dedicated, conservation-driven, and well-recognised group administration, who used the informational, relational and experiential functions of Facebook to promote individual, social and contextual pathways for pro-environmental action. Fisheries scientists and managers should consider social media interventions as an important “softer approach” to aid in management of recreational fisheries. The approach should, however, be carefully considered and include the identification and engagement with suitable groups, baseline assessments of attitudes and behaviour to identify areas of concern and the design of interventions specific for social media.