This book is about the various factors that influence the population levels of wild birds, explaining why bird numbers vary in the way they do, from year to year or from place to place. It describes the role of territorial and other behaviours in influencing local densities, as well as the role of food-supplies, nest-sites, predation, disease and competition in limiting overall population levels. The many human impacts on bird populations, including those resulting from habitat destruction and fragmentation, pollution and pesticide use, and hunting are also discussed. The final chapter deals with the problems of extinction, highlighting the various factors involved.
The book is mainly based on the findings of a host of field studies, interpreted in the light of contemporary ecological theory. Thus it provides a fresh and informed synthesis of a mass of scattered information from around the world, presenting it in a clear and coherent manner. No other book gives such an up-to-date and comprehensive treatment of this important subject.
Despite the breadth and complexities of the area, the book is written in clear and simple language. It should therefore be of value not only to the research worker and student, but also to those concerned with the practical management of bird populations (whether for hunting, crop protection or conservation), as well as to those interested in bird-watching as a hobby.