I.R. Grimwood, pers. The Kadas formerly relied on minor forest produce, but are now mainly forest labourers, as forest produce is no longer available on the same scale. Tending operations in plantations do not provide employment throughout the year and the community is very poor. The Muduvas are mainly agriculturalists, growing rice, corn and ragi etc., but they also collect some minor forest produce. The Malai-malsars are employed as forest labourers, mahoots and guides.
Villagers are dependent on the forests within and around the sanctuary for fuelwood.
About 200 cattle owned by Parambikulam Aliyar Project Colony residents, Thunacadavu inhabitants and taungya cultivators graze in the interior of the sanctuary. There are some 10,000 visitors annually. The other two dams will also have an impact on the sanctuary's wildlife due to their proximity. For example, significant amounts of evergreen forest will be submerged, possibly adversely affecting the lion-tailed macaque, an obligate evergreen forest dweller. Collection of bamboo and other forest products and taungya cultivation, although authorised, are often not conducted in accordance with prescribed scientific guidelines or exceed stipulated amounts.