Bird Study – Dealing With The Rodent Pests

In addition to weeds and insects, there is yet another group of pests, some representatives of which may be found in every neighborhood. It is composed of rabbits, ground squirrels, prairie dogs, mice, and the like. They all possess long front teeth for gnawing, and constitute the Order of Rodents. Some species destroy fruit trees by gnawing away the bark near the ground, others attack the grain stacked in the field or stored in the granary. As these little sharp-eyed creatures are chiefly nocturnal in their habits, we seldom see them; we see only the ruin they have wrought. In some of the American ports incoming vessels are systematically fumigated to kill the rats for fear they may bring with them the bubonic plague. In April, 1898, while engaged in field natural history work in Hyde County, North Carolina, I found the farms along the north shore of Matamuskeet Lake were overrun by swarms of large brown rats that burrowed in the ground everywhere, and coming out at night wrought havoc and destruction on the farm lands. The whole country was up in arms and the farmers were appealing for State and Federal aid to help them rid the land of this terrible scourge. In short, the rodents, as a class, are regarded as decidedly detrimental to the interests of mankind.

The Terror That Flies by Night.—Among the chief enemies of rodents in North America are the nineteen species of Owls, untold numbers of which are abroad every night searching through fields and forests for just such creatures as these. The digestive processes of Owls are such that the hard, indigestible portions of their food are disgorged in the form of balls and may often be found beneath their roosting places. One of our most odd-looking birds is the Barn Owl. Being nocturnal in its habits it is rarely seen unless one takes the trouble to climb into unfrequented church towers, the attics of abandoned buildings, or similar places which they seek out for roosting purposes. Some years ago the naturalist, Dr. A. K. Fisher, discovered that a pair of Barn Owls had taken up their abode in one of the towers of the Smithsonion Institution building. He found the floor thickly strewn with pellets composed of bones and fur which these birds and their young had disgorged. He collected two hundred of these and took them to his laboratory. A painstaking examination showed that they contained four hundred and fifty-three skulls. Here is his list made out at the time: two hundred and twenty-five meadow mice, two pine mice, twenty shrews, one star-nosed mole, and one Vesper Sparrow. It is plain to be seen that great good was accomplished in the community by this pair of Owls and their young, for the evil effects of the rodents in life must have far overbalanced the good service of the one useful Vesper Sparrow.

A Seldom Recognized Blessing.—There are some large predatory birds which destroy the lives of many game birds and others of the weaker species. On game farms, therefore, an unpleasant but necessary task is the shooting or trapping of Hawks and Owls. At first thought it might seem best to wage a war of absolute extermination on these offenders, and some game-keepers urge that this should be done. Personally I am opposed to any such course of action, one reason being that this would not necessarily forward the best interests of the game birds it is desired to serve. So important and yet so unexpected is the ultimate effect of the activities of predatory creatures that in a state of nature I am convinced the supply of game birds is increased rather than decreased by being preyed upon. Like all other creatures, birds are subject to sickness and disease, but by the laws of nature it appears that they are not designed to suffer long. Their quick removal is advisable if they are to be pre-vented from spreading contagion among their fellows, or breeding and passing on their weakness to their offspring. Sometimes the Hawk, dashing at a covey of game birds, may capture one of its strongest and healthiest members, but the chances are that the afflicted member, which is not so quick on the rise or is a little slower on the wing, is the one to be taken. Just as some savages are said to put to death the incompetent and unfit, so do the laws operate which govern wild life. If, therefore, we should destroy all the Hawks, Owls, wild cats, foxes, skunks, snakes, and other predatory creatures, it is an open question whether in the long run our game birds would be the gainers thereby.

Some time ago I visited a large game farm in one of the Southern States, where for several years the owner had been engaged in raising English Ring-necked Pheasants. The gamekeeper stated that there were about six thousand of these brilliantly coloured birds on the preserve at that time. He also pointed with pride to an exhibit on the walls of a small house. An examination showed that the two sides and one end of this building were thickly deco-rated with the feet of Hawks, Crows, Owls, domestic cats, minks, weasels, and other creatures that :were supposed to be the enemies of Pheasants. Two men were employed on the place to shoot and trap at all seasons, and the evidences of their industry were nailed up, to let all men see that the owner of the big game farm meant to allow no wild bird or animal to fatten on his game birds.

A year later I again visited the same preserve and found great lamentation. More than five thousand Pheasants had been swept away by disease within a few weeks. Is it going too far to say that the gun-men and trappers had overdone their work? So few Hawks or Owls or foxes had been left to capture the birds first afflicted, that these had been permitted to associate with their kind and to pass on weakness and disease to their offspring until the general health tone of the whole Pheasant community had become lowered. In the end five-sixths of the birds had succumbed to the devastations of disease.

All birds have their part to play in the great economy of the earth, and it is a dangerous experiment to upset the balance of Nature.