I am greatly indebted to the following friends, correspondents and professionals who encouraged my efforts, gave unstintingly of their time, and provided reference material or further contacts, much food for thought and clarification, and useful comment; Sid Cowling, Clifford and Dawn Frith, Graham Fulton, Peter Higgins, Stephen Marchant (Australia), Laurent Raty, Karel Tops (Belgium), Fernando C. Straube, Héctor Bottai (Brazil), Paul Clapham, Normand David, Bruce Cruickshank (Canada), Isis Benítez (Cuba), Laurent Chevrier, Jim Gaudin, Jean Grasseau, Robert Dowsett, Christophe Gouraud, Dominique Malécot, Daniel Philippe, Michel Ratteau (France), Eberhard Mey, Wolfgang Antweiler, Klaus D. Mörike, Martin Schneider, Frank Steinheimer, Stefan Weil (Germany), Aasheesh Pittie (India), Carlo Violani (Italy), Takashi Hiraoka, Minoru Chiba, Hirokatsu Nagai, Koichi Ohashi, Nobuhiko Osawa (Japan), Smathi Chong (Malaysia), José Alberto Lobato García (Mexico), Revd. Fr. Jilis Verheijen, Klaas J. Eigenhuis, René Dekker, Justin Jansen, Thierry Jansen, Jan van der Brugge, Jan B. Kaiser, Cees C. Roselaar, Frank Rozendaal, Fred Ruhe, Bas van Balen, Joost Brouwer (Netherlands), Paul Scofield (New Zealand), Marek Borkowski (Poland), António Baptista de Sousa, Paul “Alec” Zino (Portugal), Rob Guy (RSA), Juan A. García Pertegaz (Spain), Tommy Tyrberg, Björn Bergenholtz, Per Ericson, Axel Billing (Sweden), Peter Holt (Switzerland), Sheng-Shan Lu (Taiwan), Barry and Jan Jobling, Arthur Smith, Edward Dickinson, John and Christine Byrne, Alan Ford, Carol and Alan Starr, Eric Petrie, Frances “Effie” Warr, Alison Harding, Michael Walters, Robert Prŷs-Jones, Desmond Allen, Bob Foskett, Paul Gaffan, Peter Boyce, Robert W. Campbell, Robert A. Cheke, Peter Colston, Clemency Fisher, Guy Kirwan, Richard Klim, Clive Mann, Richard and Barbara Mearns, Amberley Moore, Timothy J. Phipps, George Ba-Tin, Clive Humphreys, Nigel Cleere, Caroline Lewis, Robert Neidhardt, Nigel Redman, David Snow, Mike Earp, Andy Elliott (UK), David Albeck, John H. Boyd III, Andrew Esposito, Mark Brown, John Farrand, Jr., Andy Kratter, Susan Manchester, Jeffrey S. Marks, Storrs L. Olson, A. Alan Peterson, Michael Rieser, Rose Ann Rowlett, and Rick Wright (USA). My e-mail correspondence with Bo Beolens, Michael Grayson, and Michael Watkins (UK) has been especially enlightening and fruitful, as has that of the dedicated international stalwarts of BirdForum who are acknowledged in the various entries. I must also highlight the incomparable resource that is Biodiversity Heritage Library (BHL) and encourage readers to support it. No praise is high enough for the expertise and guidance of Ferran Gil of Lynx Edicions, and the encouragement, professionalism and enthusiasm of Brian L. Sullivan, Jeff A. Gerbracht, and Laura M. Kammermeier of the Cornell Lab of Ornithology are to be commended on facilitating the smooth transition of The Key.
James A. Jobling