'As has been true with past volumes in this series, and as is particularly true this year for workers in the fields of conservation/population biology, energy studies, and studies of the evolution and ecology of behavior and social organization, Current Ornithology is not just 'for the birds' anymore.' Bioscience, March 1991 'The volume is excellent, and the extensive literature reviews provided at the end of each chapter make this valuable for anyone initiating a research study on one of the topics discussed.' The Wilson Bulletin, June 1991 'Volume 7 is a valuable reference.' Journal of the British Ornithologists' Union, 1990