PREFACE
Frederick C. Lincoln's classic work on the "Migration of Birds" first appeared in 1935. It was revised in 1950 and has been out of print for several years, after selling over 140,000 copies. Unfilled requests by many individuals, clubs, and institutions prompted the Office of Conservation Education (now the Office of Public Affairs) in the U.S. Fish and Wildlife Service to petition another update for reissue. This publication incorporates the results gathered by research biologists in the U.S. Fish and Wildlife Service to meet these requests.
Lincoln's original intent was to present to the American public a summary of the facts on bird migration as they existed in the early 1930's. He wrote with a style that made the topic fascinating to the young and old, to the educated and uninformed, and to the ardent observer as well as the backyard watcher. An attempt has been made to retain this style, while incorporating material from often highly technical research efforts. Much of the content and organization of the original publication has been maintained, but new sections were added to incorporate recent concepts and techniques. Other concepts, known to be inconsistent with present knowledge, have been deleted. Because graphics are of utmost importance in this type of publication, most of the original figures were preserved and, where appropriate, new illustrations have been added.
Since the previous edition, tremendous progress has been made in researching and understanding bird migration; along with this increased effort has come a substantial increase in the literature devoted to the subject. Emphasis was given to reviewing literature pertaining to migration studies conducted in North America after 1950, but a number of examples from the European literature have been included to emphasize similarities and differences in migration throughout the world. Because extensive author citations tend to disrupt the flow of thought, they were kept to a minimum in the text. However, this publication is essentially a review of the literature on the subject as it existed in the early 1970's, and a rather extensive bibliography has been included to cover all the papers quoted in the text as well as the many used but not specifically cited. The bibliography, then, is primarily intended for those interested in pursuing the subject further.