Résumé :
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The purpose of this book is to provide a sound, factual basis for sifting through the various perspectives on the meaning of the term " over-abundance " for populations of the two most common and widespread deer of North America, the white-tailed deer and the mule deer. Through out this volume, "deer" refers either to cervids generally or to white-trailed deer (Odocoileus virginianus) unless otherwise specified. The volume is divided into three parts, though chapters in one part often have relevance to those in others. The parts are as follows : Part One : Philosophical Perspectives, Part Two : Population Effects, and Part Three : Ecosystem Effects. The first part provides background on the issue of overabundance from profoundly divergent constituent viewpoints : wildlife biology, international conservation, state game management and animal welfare. These chapters highlight the issues involved in attempting to manage high-density deer populations, and each author draws from different sources to arrive at strikingly different conclusions. The second part includes chapters that address the demographic consequences of high densities on deer populations. These chapters pose such questions as the following. Do high densities necessarily cause reduced carrying capacity ? Are disease outbreaks a direct consequence of high density ? Are there demographic, behavioral or genetic consequences to high deer population levels ? Is it possible to determine if populations are self-regulating. Do the classic paradigms fit the data from real populations. Chapters in the third part examine the influence deer have on their environment, including the following questions. 1) Does deer browsing determine the succession patterns of old field or forest systems ? 2) Is the abundance of specific woody species or bird species influenced by deer abundance ? 3) Can deer populations serve as a reservoir for transmission of diseases to other species ? 4) Does vegetation biomass regulate the abundance of herbivores ? 5) Can the impact of deer on forest resources be predicted by density or must forage availability also be considered ? 6) How do landscape features influence the dispersion of deer ? The last chapter is a synthesis by A.R.E. Sinclair on how the concept of carrying capacity may be used to tie together the many contrasting views presented in this volume.
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