HELMUT K. BUECHN andJIMMIE H. BUECHNE, The Avifauna BD1TO of Northern ^^W Latin America: A Symposium Held at the Smithsonian Institution 13-15 April 1966 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • 1970 NUMBER 26 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 26 Helmut K. Buechner The Avifauna of and Jimmie H. Buechner TVT ^I T . • A EDITORS Northern Latin America A Symposium Held at the Smithsonian Institution 13-15 April 1966 SMITHSONIAN INSTITUTION PRESS CITY OF WASHINGTON 1970 SERIAL PUBLICATIONS OF THE SMITHSONIAN INSTITUTION The emphasis upon publications as a means of diffusing knowledge was expressed by the first Secretary of the Smithsonian Institution. In his formal plan for the Insti- tution, Joseph Henry articulated a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge not strictly professional." This keynote of basic research has been adhered to over the years in the issuance of thousands of titles in serial publications under the Smithsonian imprint, commencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Annals of Flight Smithsonian Contributions to Anthropology Smithsonian Contributions to Astrophysics Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Z°°l°iy Smithsonian Studies in History and Technology In these series, the Institution publishes original articles and monographs dealing with the research and collections of its several museums and offices and of professional colleagues at other institutions of learning. These papers report newly acquired facts, synoptic interpretations of data, or original theory in specialized fields. Each publica- tion is distributed by mailing lists to libraries, laboratories, institutes, and interested specialists throughout the world. Individual copies may be obtained from the Smith- sonian Institution Press as long as stocks are available. S. DILLON RIPLEY Secretary Smithsonian Institution Official publication date is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON : 1970 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price $3.25 Foreword This conference was conceived by William Vogt, who is well known for his early concern with the ecological consequences of the human population explosion, as expressed in his book Road to Survival (New York: William Sloane Associates, 1948). Over three decades of field observation in Latin America have provided him with a view of environmental changes, particularly the destruction of forest vegetation, that few other scholars have experienced. The conference was convened to determine, through an exchange of information, whether the drastic modification and elimina- tion of the wintering habitat of many breeding birds of North America may be responsible for depressed levels of populations. The assemblage of most of the outstanding scholars of bird life in Central America, Colombia, and Venezuela at the Smithsonian Institution resulted in a remarkable accumulation of information and exchange of ideas. Fourteen individual papers were presented, each of which was followed by discussion. Further discussion took place in a plenary session after the papers on the individual countries. In lieu of resolutions the conferees agreed on a series of suggestions which are presented in tiese proceedings. The conference was organized by the Smithsonian Office of Ecology, and made possible by a generous grant from the Conservation Foundation. We would like to express our gratitude to Paul Slud, Associate Curator, Division of Birds, National Museum of Natural History, for verifying the spelling of scientific names and for his considerable assistance with the final editing. THE EDITORS m Contents Page Foreword iii List of Participants vii Prefatory Statement, S. Dillon Ripley 1 The Meaning of Environment, Marston Bates 3 The Avifauna in a Changing Ecosystem, William Vogt 8 Discussion 13 Changing Abundance of Migratory Birds in North America, John W. Aldrich and Chandler S. Robbins 17 Discussion 25 Natural Vegetation and Reservation Prospects in Northern Latin America, L. R. Holdridge 27 Discussion 30 The Future of Avifauna in Guatemala and Its Relation to Tourism, Jorge A. Ibarra 34 Discussion 37 Effects of Habitat Changes on Population Levels of the Avifauna in Honduras, Burt L. Monroe, Jr 38 Discussion 41 Avifauna in British Honduras, Stephen M. Russell 45 Discussion 48 Avifauna in Panama, Eugene Eisenmann 50 Discussion 55 Avifauna in Nicaragua, Thomas R. Howell 58 Discussion 61 Mexico: Avifauna and Modification of Habitat, Rodolfo Herndndez Corzo. 63 Discussion 67 Avifauna in Mexico, Allan Phillips 69 Discussion 72 Avifauna in Venezuela, William H. Phelps, Jr 75 Discussion 76 Effects of the Environmental Changes on the Avifauna of the Republic of Colombia, Antonio Olivares, O.F.M 77 Discussion 84 Avifauna in Colombia, F. C. Lehmann 88 Discussion 90 Page Closing Plenary Session 93 Suggestions Emanating from the Conference on Avifauna of Northern Latin America 108 Appendix (1969) Ill Index 113 List of Participants MARSTON BATES ARMANDO DUGAND Department of Zoology Institute of Scientific Investigation University of Michigan Apartado Arereo Ann Arbor, Mich. 48104 1890Baranquilla Colombia, S.A. JAMES BOND Department of Ornithology EUGENE EISENMANN Academy of Natural Sciences of Philadelphia Department of Ornithology Philadelphia, Pa. 19103 American Museum of Natural History New York, N.Y. 10024 MARIA BUCHINGER Latin American Natural Area Programs F. RAYMOND FOSBERG Nature Conservancy Director's Office 1701 18thSt.N.W. Museum of Natural History Washington, D.C. 20009 Smithsonian Institution Washington, D.C. 20560 HELMUT K. BUECHNER Office of Ecology IRA GABRIELSON Smithsonian Institution World Wildlife Fund Washington, D.C. 20560 710 17th St. N.W. Washington, D.C. 20006 VICTOR H. CAHALANE Route 1, Box 234C EDWARD H. GRAHAM (deceased) Alexandria, Va. 22313 Commission on Ecology of the International Union for Conservation of Nature and Natural Resources ROLAND C. CLEMENT Washington, D.C. 20036 National Audubon Society 1130 5th Ave. JAMES C. GREENWAY, JR. New York, N.Y. 10028 Mead's Point Greenwich, Conn. 06830 HAROLD J. COOLIDGE National Academy of Sciences LESLIE R. HOLDRIDGE National Research Council Tropical Science Center Pacific Science Board San Jose, Costa Rica Washington, D.C. 20008 THOMAS R. HOWELL RODOLFO HERNANDEZ CORZO Department of Zoology Direccion General de Caza University of California Aquiles Serdan 28, 70 Piso Los Angeles, Calif. 90024 Mexico 3, D.F. Mexico PHILIP S. HUMPHREY ROBERT S. DORNEY Director Department of Geography and Planning Museum of Natural History University of Waterloo University of Kansas Waterloo, Ontario, Canada Lawrence, Kansas 60644 Vlll SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY JORGE A. IBARRA LESTER L. SHORT Museo Nacional de Historia Natural Department of Ornithology Guatemala City, Guatemala American Museum of Natural History New York, N.Y. 10024 HUGH G. LAND Department of Biological Sciences PAUL SLUD Northwestern State College of Louisiana Division of Birds Natchitoches, La. 71457 Museum of Natural History Smithsonian Institution CARLOS LEHMANN Washington, D.C. 20560 Museo Departmental de Historia Natural Cali, Colombia ALEXANDER SPRUNT IV National Audubon Society BURT L. MONROE, Jr. Box 231 Department of Zoology Tavernier, Florida 33070 University of Louisville Louisville Ky. 40508 LLOYD W. SWIFT 3432 Greentree Drive MARTIN H. MOYNIHAN Falls Church, Va. 22041 Smithsonian Tropical Research Institute P.O. Box 2072 LEE M. TALBOT Balboa, C.Z. Office of Ecology Smithsonian Institution ANTONIO OLIVARES, O.F.M. Washington, D.C. 20560 Department of Ornithology WILLIAM VOGT (deceased) Instituto de Ciencias Naturales The Conservation Foundation Bogota, Colombia 1250 Conn. Ave.N.W. ROGER T. PETERSON Washington, D.C. 20036 Neck Road WILLIAM W. WARNER OldLyme, Conn. 06371 Office of International Activities Smithsonian Institution WILLIAM H. PHELPS, JR. Washington, D.C. 20560 Coleccion Ornithologica Phelps Apartada 2009 GEORGE E. WATSON Caracas, Venezuela Division of Birds Museum of Natural History ALLAN PHILLIPS Smithsonian Institution Mexico D.F., Mexico Washington, D.C. 20560 S. DILLON RIPLEY ALEXANDER WETMORE Secretary Division of Birds Smithsonian Institution Museum of Natural History Washington, D.C. 20560 Smithsonian Institution Washington, D.C. 20560 PHILIP RITTERBUSH DAVID B. WINGATE Office of Academic Programs GPO Box 437 Smithsonian Institution Hamilton, Bermuda Washington, D.C. 20560 RICHARD L. ZUSI STEPHEN M. RUSSELL Division of Birds Department of Zoology Museum of Natural History University of Arizona Smithsonian Institution Tucson, Ariz. 85721 Washington, D.C. 20560 Prefatory Statement S. Dillon Ripley The idea for this conference to assess the conserva- Robert MacArthur, who attempted to assess the win- tion of avifauna of northern Latin America sprang ter ranges of warblers in which he was interested, and I from the fertile mind of William Vogt, who questioned remember descriptive and agonizing portrayals of the what happens to North American migrating birds on trials and tribulations of migrating warblers