Environment and the Earth

This chapter introduces the concept of stress for wild animals. The answer to the question posed at the beginning of this chapter—what is stress?—is not simple. It requires an idea of what environmental changes animals must cope with, knowledge of different life-history stages, and an understanding of how animals initiate an emergency life-history stage in order to cope with labile perturbation factors. One take-home message is that the stress response, or the emergency life-history stage, is part of a continuum of how animals cope with a changing environment. The focus of this book is on the specific physiological, hormonal, and behavioral responses to labile perturbation factors, but one must always keep in mind that the ultimate goal of each and every stress response is to return the animal to its appropriate life-history stage.