Two groups of tribes, Muthuvans and Hill Pulayas, inhabit the sanctuary in 11 hamlets or kudies.The life world of the two tribal communities are very different. The Sanctuary provides the livelihood options for the tribes and helps in maintaining their cultural heritage. Archeologically significant megalithic burial sites consisting of dolmens and cysts are found near some settlements. Being inside the Sanctuary, these 11 settlements have significant impact on the forests around them and vice versa. With the launching of the Ecodevelopment programme, successful efforts have been made for evolving a model of biodiversity conservation in a human dominated landscape. The focus of the programme is to minimize the impact of local tribel communities on the Sanctuary by involving them in its management and providing alternate means of income generation.