This book and its companion volume represent a personal statement about the ecology of bird communities – what they are, what we know about them, and what we need to know. They are also about how avian community ecology has been practiced as a science – how we have gone about gaining our knowledge of bird comunities and how logical and methodological considerations affect the certainty we can attach to that knowledge. Because studies of birds have contributed a good deal to the foundation of contemporary community ecology and because concerns about logic, methodology, and epistemology are central to any science, I believe that the themes and viewpoints I develop are relevant to community ecology well beyond the somewhat artificial boundaries dictated by my focus on birds. My topic is really community ecology as it has been practiced on birds rather than bird communities per se.

Avian community ecology is a complex, multifaceted discipline that is enriched by controversy. I have written these volumes partly in an attempt to examine the complexity of communities and to probe the dimensions of the controversies, but partly also out of a simple enjoyment of the subject. I have directed my comments particularly toward advanced undergraduates and graduate students with interests in avian community ecology or, more broadly, in birds or in ecology, for I feel that they are in the best position to put my comments into practice or to challenge my views. I hope that my colleagues – practicing ecologists – will also find much to interest (or outrage!) them.