[1] Sokoine Univ Agr, Dept Forest Biol, Morogoro 5601, Tanzania
[2] Univ Cambridge, Dept Zool, Cambridge CB2 3EJ, England
[3] Univ Leeds, Earth & Biosphere Inst, Leeds, W Yorkshire, England
[4] World Wildlife Fund, Washington, DC 20037 USA
[5] Univ York, Environm Dept, CIRCLE, York YO10 5DD, N Yorkshire, England
[6] Flamingo Land ltd, Kirby Misperton YO17 6UX, N Yorkshire, England
[7] Sokoine Univ Agr, Dept Forest Mensurat & Management, Morogoro 5601, Tanzania