1. Forest Ecology & Forest Management group; Wageningen University; P.O. Box 47 6700AA Wageningen The Netherlands
2. Instituto Boliviano de Investigación Forestal; Km 9 carretera al norte, Casilla 6204 Santa Cruz de la Sierra Bolivia
3. Department of National Parks; Wildlife and Plant Conservation; Bangkok Thailand
4. Ecology and Biodiversity; Institute of Environmental Biology; Utrecht University; Padualaan 8 3584 CH Utrecht The Netherlands