Insect Populations In Theory And In Practice

"This book seeks to fulfil the need for a concise and inexpensive text on population ecology. It presents general principles derived from demographic studies of insects in various parts, of the world, and shows how those principles bear upon the practice of ecology both in research and in the management of biological resources. The book is aimed at a wide audience including students and teachers of ecology, and economic entomologists. After reviewing the develpment of ecological thought since Darwin, the authors discuss the views advanced by modern theorists to explain how animal numbers are determined, and describe a comprehensive and functional way of envisaging the dynamics of insect populations, suited to the problems confronting most ecologists today and to modern methods of work. The authors show how their generalised model can serve for the derivation of explanatory synthesis of population dynamics in a number of cases ranging from investigations pursued under laboratory conditions to large-scale field studies. Recognised approaches to the study of numerical determination in insect populations are presented synoptically according to the characteristics of the information sought. In addition, the authors present a comprehensive discussion of pest control, in which they test the practical efficacy of their views and analyse the relation of demographic ecology to the management of pests. The book is concluded by outlining the ecological research needed to advance our understanding of insect behavior." BOOK JACKET.

Insects are by far the largest group of animals on Earth, with over a million described species, and they occupy a wide range of ecological niches - they may be herbivores, predators, parasites or decomposers. Some are of particular economic importance as pests of agriculture and forestry, as vectors of animal and human disease, or as species of interest to wildlife conservation. Thus an understanding of the processes determining their numbers is of considerable practical value. Entomologists have played a leading role in developing a theoretical basis to Population Ecology, but we still do not have adequate experimental and observational proof for many of the theoretical ideas that have been proposed. As a result, the subject has been beset with arguments for more than 50 years. This volume attempts to reconcile some of these controversies, while also reviewing the current state of our knowledge. The editors have drawn together an international list of contributors whose views reflect a range of opinions on how natural populations are stabilised. They have succeeded in producing a book that both covers the main alternative views in population theory and contains some of the best recent field studies of insect populations. This Royal Entomological Society Symposium volume will be of great interest to all entomologists and ecologists, particularly those who wish to know more about Population Dynamics.

The papers in this volume were presented at a symposium/workshop on "The Estimation and Analysis of Insect Populations" that was held at the University of Wyoming, Laramie, in January, 1988. The meeting was organized with financial support from the United States - New Zealand Cooperative Science Program and the University of Wyoming. The purpose was to bring together approximately equal numbers of quantitative biologists and biometricians in order to (1) provide a synthesis and evaluation of currently available methods for modeling and estimating parameters of insect population, and to (2) stimulate research into new methods where this is appropriate. The symposium/workshop attracted 46 participants. There were 35 papers presented in four subject areas: analysis of stage-frequency data, modeling of population dynamiCS, analysis of spatial data, and general sampling and estimation methods. New results were presented in all these areas. All except one of the papers is included in the present volume.

The abundance of insects can change dramatically from generation to generation; these generational changes may occur within a growing season or over a period of years. Such extraordinary density changes or "outbreaks" may be abrupt and ostensibly random, or population peaks may occur in a more or less cyclic fashion. They can be hugely destructive when the insect is a crop pest or carries diseases of humans, farm animals, or wildlife. Knowledge of these types of population dynamics and computer models that may help predict when they occur are very important. This important new book revisits a subject not thoroughly discussed in such a publication since 1988 and brings an international scale to the issue of insect outbreaks. Insect Outbreaks Revisited is intended for senior undergraduate and graduate students in ecology, population biology and entomology, as well as government and industry scientists doing research on pests, land managers, pest management personnel, extension personnel, conservation biologists and ecologists, and state, county and district foresters.

Expressing propulation changes; density dependent processes affecting cultures of single species; composititions between species for a limited resouce; parasites and predatrs; climate and weather; life tables and their use in population chages of some forest insects; biological control.

Combining breadth of coverage with detail, this logical and cohesive introduction to insect ecology couples concepts with a broad range of examples and practical applications. It explores cutting-edge topics in the field, drawing on and highlighting the links between theory and the latest empirical studies. The sections are structured around a series of key topics, including behavioral ecology; species interactions; population ecology; food webs, communities and ecosystems; and broad patterns in nature. Chapters progress logically from the small scale to the large; from individual species through to species interactions, populations and communities. Application sections at the end of each chapter outline the practicality of ecological concepts and show how ecological information and concepts can be useful in agriculture, horticulture and forestry. Each chapter ends with a summary, providing a brief recap, followed by a set of questions and discussion topics designed to encourage independent and creative thinking.

Insects multiply. Destruction reigns. There is dismay, followed by outcry, and demands to Authority. Authority remembers its experts or appoints some: they ought to know. The experts advise a Cure. The Cure can be almost anything: holy water from Mecca, a Government Commis sion, a culture of bacteria, poison, prayers denunciatory or tactful, a new god, a trap, a Pied Piper. The Cures have only one thing in common: with a little patience they always work. They have never been known entirely to fail. Likewise they have never been known to prevent the next outbreak. For the cycle of abundance and scarcity has a rhythm of its own, and the Cures are applied just when the plague of insects is going to abate through its own loss of momentum. -Abridged, with insects in place of voles, from C. Elton, 1924, Voles, Mice and Lemmings, with permission of Oxford University Press This book is an enquiry into the "natural rhythms" of insect abundance in forested ecosystems and into the forces that give rise to these rhythms. Forests form unique environ ments for such studies because one can find them growing under relatively natural (pri meval) conditions as well as under the domination of human actions. Also, the slow growth and turnover rates of forested ecosystems enable us to investigate insect popula tion dynamics in a plant environment that remains relatively constant or changes only slowly, this in contrast to agricultural systems, where change is often drastic and frequent.

One of the themes of the 20th International Congress of Entomology held in Florence in August 1996 was Ecology and Population Dynamics, with papers presented on single species dynamics, population interactions, and community ecology. This book contains a selection of the papers that were presented, and gives a late-1990s picture of the latest research in this fast developing area.