[1] BirdLife South Africa, Private Bag X16, ZA-2123 Pinegowrie, South Africa
[2] Royal Soc Protect Birds, Flyway Conservat Programme, Sandy SG19 2DL, England
[3] Univ South Africa, Coll Agr & Environm Sci, Sch Agr & Life Sci, Dept Life & Consumer Sci, Private Bag x6, ZA-1710 Pretoria, Florida, South Africa
[4] Univ Ghana, Dept Plant & Environm Biol, POB LG 55, Legon, Acca, Ghana
[5] Univ Nangui Abrogoua, 02 BP 801, Abidjan, Cote Ivoire
[6] Kwame Nkrumah Univ Sci & Technol KNUST, Kumasi, Ghana
[7] Univ Abomey Calavi, Fac Agr Sci, Lab Appl Ecol, 01 BP 526, Cotonou, Benin
[8] Univ Bourgogne, INRAE, UMR Agroecol, 17 Rue Sully, F-21000 Dijon, France
[9] Bhejane Adventures, Plettenberg Bay, Western Cape, South Africa
[10] Imperial Coll London, Georgina Mace Ctr Living Planet, Silwood Pk Campus, Ascot SL5 7PY, England
[11] Ctr Natl Rech Agron, Marc Delorme Res Ctr, 07 BP 13, Abidjan, Cote Ivoire
[12] Univ Tennessee, Dept Ecol & Evolutionary Biol, Knoxville, TN USA
[13] Univ Johannesburg, Dept Geog Environm Management & Energy Studies, APK Campus, Johannesburg 2006, South Africa
[14] Univ Parakou, Fac Agron, BP 123, Parakou, Benin
[15] Nottingham Trent Univ, Sch Anim Rural & Environm Sci, Nottingham, England
[16] IUCN, Cambridge, England
[17] David Attenborough Bldg, Fauna & Flora, Pembroke St, Cambridge, England
[18] Natl Univ Agr, Sch Management & Plant Seed Prod, PO 42 Box 43, Ketou, Benin
[19] Univ Rwanda, Ctr Excellence Biodivers & Nat Resource Management, Butare, Rwanda
[20] Univ Massachusetts, Sch Environm, Boston, MA USA
[21] Mabula Ground Hornbill Project, POB 876, ZA-0480 Bela Bela, South Africa
[22] IUCN Species Survival Commiss, Hornbill Specialist Grp, Rue Mauverney 28, CH-1196 Gland, Switzerland
[23] A Rocha Ghana, Kaneshie, Greater Accra R, Ghana
[24] Nat Kenya, POB 44486, Nairobi, Kenya
[25] BirdLife Int, Afr Partnership Secretariat, POB 3502, Nairobi, Kenya
[26] Univ Oxford, Dept Biol, Oxford OX1, England
[27] Agr Res Inst Dev IRAD, POB 2123, Yaounde, Cameroon
[28] Univ Dschang, Fac Sci, Dept Biochem, POB 67, Dschang, West Region, Cameroon
[29] Univ Ghana, Dept Anim Biol & Conservat Sci, POB LG25, Legon, Accra, Ghana
[30] Inst Venezolano Invest Cient & Provita, Inst Venezolano Invest Cient IVIC, Caracas, Venezuela
[31] Provita, Caracas, Venezuela
[32] Univ South Africa, Dept Agr & Environm Sci, Private Bag X6, ZA-1710 Florida, Florida, South Africa
[33] Royal Bot Gardens, Richmond TW9 3AB, England