xiv INTRODUCTION 



especially where natural population controls have been artificially removed. 

 Pearsall considers that the rational management and exploitation of wild 

 animals is potentially the most efficient form of land use in the African 

 plains, where present agricultural and pastoral practises tend to destroy 

 environmental fertiUty. 



The economic and practical importance of wild animals provides abundant 

 justification for the study of their populations by ecologists, but there are 

 also other reasons. The large scale on which exploited animals are taken 

 provides the biologist with abundant samples for study, and when some 

 record has been kept of the catches, invaluable statistical information about 

 secular changes in abundance may be available. An ecologist studying other 

 organisms, who has to collect his own samples every week for fifty years 

 may well feel envious ! Furthermore, observation alone of a relatively stable 

 population will not usually lead to an understanding of its regulatory 

 mechanism: some kind of disturbing influence is needed. Climatic trends or 

 year to year variations may be useful, but artificially induced disturbances 

 can be much more revealing. Exploitation by man is such a disturbance and 

 can often constitute an experiment in population dynamics. (Paradoxically, 

 it was the cessation of fishing in the North Sea during the two world wars 

 that revealed many of the effects of exploitation on fish populations.) 



The exploitation of animals thus provides ecologists with fmancial support 

 to work on a wide range of animal species, abundant material to study, and 

 experiments to observe. The following pages may be offered as a sample of 

 what population ecologists have made of these opportunities, and how far 

 they have progressed towards an understanding of the scientific basis of the 

 response of natural animal populations to exploitation. 



