Game Management

V. GAME RANGE¹

CHAPTER V GAME RANGEl What Is Game Rangel When the game manager asks himself whether a given piece of land is suitable for a given species of game, he must realize that he is asking no simple question, but rather he is facing one of the great enigmas of animate nature. An answer good enough for practical purposes is usually easy to get by the simple process of noting whether the species is there and ready, or whether it occurs on "similar" range nearby. But let him not be cocksure about what is "similar," for this involves the deeper questions of why a species occurs in one place and not in another, which is probably the same as why it persists at all. No living man can answer that question fully in even one single instance. It should be realized, first of all, that the present boundaries of the ranges of our present species constitute a great maze of diversities. If all species boundaries were plotted on a great map of the world, it would look like a wide pavement on a wet morning, after thousands of earthworms had been crawling over it all night, inscribing their irregular tracks. Secondly, although the boundaries of these present ranges seem so stable to us that we record them in books and maps as fixed facts of nature, they have as a matter of fact undergone continuous change through the ages, each change constituting the response of the species to some change in its environment or in itself. Grinnell, in his essay ..Presence and Absence of Animals" (1928) portrays with classical lucidity this march and countermarch of wild-animal armies across the long battlefield of time. A species, he says, does not shift or wander; it is herded about by the compelling orders of circumstance. It survives only where and when it finds an "ecologic niche," or "set of conditions which provide adequate means of subsistence for the particular species, and which that species can tolerate." 1 Parts of this chapter appeared as an article in TAl JO"",III of For,stry, VoL XXIX No.6, October, 1931. 114 GAME R.ANGE 125 Friedman (1931) describes the interplay of factors determining "range" in terms of an elaborate analogy: "'We may ... compare ... the distribution of birds to a symphony played by a great orchestra.... Each instrument ... is ... one factor ... in the environment.... At anyone moment the individual sounds ... of the many instruments ... fuse and blend to form one auditory effect. This is comparable to the range of one species (at any one time). No two instants are exactly alike in their sound summations, just as the distributions of no two species are ever wholly similar. In the production of certain sounds all the instruments may be combined; in others, only certain ones; in others, two of the component sounds may be mutually interfering and obliterate each other. In other words •.. each present distributional fact represents a polyphony of causes." The game manager seeks to alter one of the sounds for one geological instant for the benefit of man. He seeks to make one biologic niche a little more tenable than that resulting from the "fortuitous concourse" of man and nature. How sliall he go about it? He cannot really understand" the polyphony ofcauses" which determine the range (and abundance) of a species, but he can manipulate the more obvious features of the environment with at least partial intelligence by comparing them WIth what determines his own range and abundance. He can postulate, for instance, that for a piece of land to be habitable by game it must offer places suitable for feeding, hiding , resting, sleeping, playing, and raising young. The essential difference between a deer and a man is that man builds farms, factories, and cities to provide himself with the elements of an habitable range, whereas a deer must accept the random assortment laid down by nature and modified by human action, or move elsewhere. In both cases that endless competition which we call society consists essentially in a struggle for the best assortment of places to feed, hide, rest, sleep, play, and breed. If the assortment of environmental types in anyone locality falls short of being adequate to maintain thrift and welfare, the species shrinks in numbers to what the locality will support. When such shrinkage approaches zero, the locality is lost altogether , and the species withdraws. When such withdrawals become too prevalent, the species becomes extinct. Environmental Types. Each species requires...