Competition and the Structure of Bird Communities. (MPB-7), Volume 7


Book Description

Professor Cody's monograph emphasizes the role of competition at levels above single species populations, and describes how competition, by way of the niche concept, determines the structure of communities. Communities may be understood in terms of resource gradients, or niche dimensions, along which species become segregated through competitive interactions. Most communities appear to exist in three or four such dimensions. The first three chapters describe the resource gradients (habitat types, foraging sites, food types), show what factors restrict species to certain parts of the resource gradients and so determine niche breadths, and illustrate the important role of resource predictability in niche overlap between species for resources they share. Most examples are drawn from eleven North and South American bird communities, although the concepts and methodology are far more general. Next, the optimality of community structure is tested through parallel and convergent evolution on different continents with similar climates and habitats, and the direct influence of competitors on resource use is investigated by comparisons of species--poor island communities to species-rich mainland ones. Finally, the author discusses those sorts of environments in which the evolution of one species--one resource set is not achieved, and where alternative schemes of resource allocation, often involving several species that act ecologically as one, must be followed.




Habitat Selection in Birds


Book Description

The present book is divided into several parts. An introductory chapter serves to make the reader aware of the diversity of the subject of habitat selection in birds. Many if the various aspects of habitat selection introduced in the first chapter are developed in subsequent chapters, and thus it serves to some extent as an overview of the subject and as a "lead-in" to subsequent work.




The Ecology of Bird Communities


Book Description

A major study of avian community ecology.




Interspecific Competition in Birds


Book Description

Provides a current, critical review of the importance of interspecific competition, considering the evolutionary effects of interspecific competition, its importance in structuring communities, and influence on the traits of individual species.




Ecological Communities


Book Description

This work is the first to focus systematically on a much-debated topic: the conceptual issues of community ecology, including the nature of evidence in ecology, the role of experiments, attempts to disprove hypotheses, and the value of negative evidence in the discipline. Originally published in 1984. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.




Competition and Coexistence


Book Description

The question "Why are there so many species?" has puzzled ecologist for a long time. Initially, an academic question, it has gained practical interest by the recent awareness of global biodiversity loss. Species diversity in local ecosystems has always been discussed in relation to the problem of competi tive exclusion and the apparent contradiction between the competitive exclu sion principle and the overwhelming richness of species found in nature. Competition as a mechanism structuring ecological communities has never been uncontroversial. Not only its importance but even its existence have been debated. On the one extreme, some ecologists have taken competi tion for granted and have used it as an explanation by default if the distribu tion of a species was more restricted than could be explained by physiology and dispersal history. For decades, competition has been a core mechanism behind popular concepts like ecological niche, succession, limiting similarity, and character displacement, among others. For some, competition has almost become synonymous with the Darwinian "struggle for existence", although simple plausibility should tell us that organisms have to struggle against much more than competitors, e.g. predators, parasites, pathogens, and envi ronmental harshness.




Ecology and Conservation of Birds in Urban Environments


Book Description

This book provides syntheses of ecological theories and overarching patterns of urban bird ecology that have only recently become available. The numerous habitats represented in this book ranges from rows of trees in wooded alleys, to wastelands and remnants of natural habitats encapsulated in the urban matrix. Authored by leading scientists in this emergent field, the chapters explore how the characteristics of the habitat in urban environments influence bird communities and populations at multiple levels of ecological organization and at different spatial and temporal scales, and how this information should be incorporated in urban planning to achieve an effective conservation of bird fauna in urban environments. Birds are among the most conspicuous and fascinating residents of urban neighborhoods and provide urban citizens with everyday wildlife contact all over the world. However, present urbanization trends are rapidly depleting their habitats, and thus knowledge of urban bird ecology is urgently needed if birds are to thrive in cities. The book is unique in its inclusion of examples from all continents (except Antarctica) in an effort to arrive at a more holistic perspective. Among other issues, the individual chapters address the censusing of birds in urban green spaces; the relationship between bird communities and the structure of urban green spaces; the role of exotic plant species as food sources for urban bird fauna; the influence of artificial light and pollutants on bird fauna; trends in long-term urban bird research, and transdisciplinary studies on bird sounds and their effects on humans. Several chapters investigate how our current knowledge of the ecology of urban bird fauna should be applied in order to achieve better management of urban habitats so as to achieve conservation of species or even increase species diversity. The book also provides a forward-looking summary on potential research directions. As such, it provides a valuable resource for urban ecologists, urban ecology students, landscape architects, city planners, decision makers and anyone with an interest in urban ornithology and bird conservation. Moreover, it provides a comprehensive overview for researchers in the fields of ecology and conservation of urban bird fauna.










Current Ornithology


Book Description

It is not often that a century of scholarly activity breaks conveniently into halves, but ornithology of the first half of the 20th century is clearly different from that of the second half. The break actually can be marked in 1949, with the appearance of Meyer and Schuz's Ornithologie ais Biologische Wissenschaft. Prior to this, ornithologists had tended to speak mostly to other ornithologists, experiments (the testing of hy potheses) were uncommon, and a concern for birds as birds was the dominant thread in our thinking. Subsequent to 1949, ornithologists have tended to become ever more professional in their pursuits and to incorporate protocols of experimental biology into their work; more importantly perhaps, they have begun to show a concern for birds as agencies for the study of biology. Many of the most satisfying of recent ornithological studies have come from reductionist research ap proaches, and have been accomplished by specialists in such areas as biochemistry, ethology, genetics, and ecology. A great many studies routinely rely on statistical hypothesis testing, allowing us to come to conclusions unmarred by wishful thinking. Some of us are ready to tell the world that we are a "hard" science, and perhaps that time is not so very far off for most of us. Volume 2 examines several solid examples of late 20th-century ornithology.