Athough dated (1974 publication) this book is very valuable for complete understanding of the nature of being a bird, and therefore enables more informed, and sensitive watching. As promised in the preface or forward it is easy to read. I greatly appreciated the author's environmental conscience. I am saddened by the realization that with regard to environmental preservation,protection, concern, we are not much advanced these 39 years later. We are some and that's better than backwards but so far to go.