1. International Union for Conservation of Nature (IUCN) Species Survival Commission, 1196 Gland, Switzerland; United Nations Environmental Programme World Conservation Monitoring Centre, Al Ain Wildlife Park and Resort, Al Ain, United Arab Emirates; and Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
2. Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA.
3. IUCN, 1196 Gland, Switzerland.
4. Conservation International, Arlington, VA 22202, USA.
5. Centro de Ecología, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A, Venezuela, and Provita, Apartado 47552, Caracas 1041-A, Venezuela.