- Historic Sites
A Heritage In Peril
In a mere three hundred years we have despoiled a rich continent and seriously disturbed its balance of life. Nature may not let us escape the consequences much longer
August 1966 | Volume 17, Issue 5
True, man has the primary claim to the land. But in making use of the land he has too often destroyed its natural variety, coupled conservation of game with the killing of predators, and then broadcast poisons to cut down the resulting overpopulations of pests. Some of these compounds, applied directly or by plane over 89.5 million acres every year, are so stable that they circulate through food chains for years. Rachel Carson’s prophecy of a silent spring has come true in many communities where robins and insect-eating birds have sharply declined or disappeared; and massive fish kills on the lower Mississippi dramatize the threat to our own food supply, for man himself stands at the end of a food chain. “If man refuses to follow wise conservation practices in controlling his economic affairs, the ultimate victim may be not natural beauty or birds and fish but man himself,” said the New York Times recently, repeating a warning issued by Secretary of the Interior Stewart L. Udall. “Unless man, the giant predator, becomes the farsighted conservator of this planet, he may join the whooping crane, the great blue whale and the golden eagle as a threatened species.”
Prey and Predators: A Balance Upset
Far-sighted conservation policy must recognize a central fact: that the control of nature depends on a balance between prey and predators. Yet all too often in the white man’s tenure on this continent, such conservation as he has practiced has been in the nature of response to emergencies, with little regard for the long-run ecological balance.
A repeated victim of the resulting confusion has been the deer, one of America’s most beautiful wild creatures, a source of food for Indians and pioneers, and, in latter days, one of our prime game animals. In the eastern deciduous forest of 1600, the white-tailed deer population varied from about 100 to 840 per ten square miles. One or two wolves or cougars in the area kept the number of deer stable by killing off about a quarter of them each year. But as the land was settled and the wilderness shrank, these predators disappeared. The cougar, whose hunting range is twenty to sixty miles, and the wolf, whose range is ten to twenty, had no place to go except to cultivated areas, where they were shot as a menace to game and livestock. Bobcats, who prey on very young, sick, or old deer, could not take their place, nor could the omnivorous black hears, foxes, raccoons, skunks, and opossums.
So, as the nation flowed westward, deer increased on the abandoned eastern hill farms and in the lumbered-off forests. At the same time, they were protected by game laws: as early as 1677 Connecticut placed restrictions on killing them and exporting their skins; similar legislation followed dose on the retreating frontier, reaching California in 1850.
By 1880 on Mt. Desert Island in Maine, there were too many deer, and wholesale starvation occurred six years later, during winter ice storms. The Adirondacks experienced their first irruption in 1896, about a decade after the wolves and cougars were gone. In the West, the first recorded irruption of mule deer, on the Kaibab Plateau of Arizona occurred in 1924, fourteen years after government predator-control had exterminated hundreds of cougars and wolves. The herd grew from about 4,000 to 100,000 until meadows and coniferous forests were overbrowsed and mass starvation ensued. By 1938, the number of deer had dropped 10,000. The Kaibab then became a matter of national concern; the range was expanded and replanted, predators were allowed to come in from the surrounding territory, and limited hunting was restored. As a result, this national forest now supports a deer population of about 13,000.
The lesson of the Kaibab, however, came too late. Well into the mid-twentieth century one hundred trouble spots, varying in size from a small refuge to half a state, suffered deer irruptions; of these, nearly half reported a “crash” in numbers from starvation, and the rest alleviated their problem temporarily by allowing; open season on does. Only one-tenth claim to have restored a balanced community, however; all the rest are irreparably out of step. When the shrubs have grown up again, there will be more population peaks, followed by more crashes. When game managers warn of an impending irruption, state legislatures are fearful of increasing bag limits because of almost certain political censure later on, when it may become necessary to lower them again. Hunters, it seems, cannot even begin to control deer populations.
But most of us are not hunters, and the number of dedicated deer-watchers is limited. If the confusion in our efforts to control nature were limited to game laws, the apathy of the general public would perhaps be understandable. Unfortunately, it does not stop there: it extends to our use of our western ranges, to our agricultural methods, even to our tending of lawns and gardens. Our indiscriminate use of pesticides still threatens a silent spring which might fundamentally alter the kind of America in which most of us want to live.