For nearly a century, researchers have observed the ecological impacts arising from increased numbers of visitors using natural areas for tourism and recreational activities. This study reviews the recreational ecology literature as it is relevant to Sri Lanka providing a rare linkage between global research and local applications of this research. The likely ecological impacts of recreational activities undertaken in natural areas in Sri Lanka are identified with a particular focus on walking/hiking, camping, wildlife watching and motorized activities. We conclude by establishing a research agenda that is relevant for developing countries from the Global South and South Asia that aspire to develop their nature-based tourism industry in a sustainable manner. A particular focus should be on fundamental visitor data collection and relating such data to environmental impacts of specific recreation activities, the establishment of research networks, experimental cause-effect studies, and interdisciplinary studies. We embed this research agenda in a novel conceptual model of the factors and relationships relevant for managing impacts of nature-based tourism as a theoretical contribution to the field of recreational ecology.