Forest Preserve District of Cook County, Illinois
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Exotic Animals
Nature Bulletin No. 440-A   January 15, 1972
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation

When people settle in a new land they always bring to it plants and animals that are strangers there. The early colonists in North America brought the seeds of grains, grasses, clovers, garden crops and flowers they grew in Europe. They brought horses, cattle, sheep, goats, swine, poultry, cats and dogs. They brought honeybees because there were none here. Unfortunately, mixed with their seeds or in forage for their animals, they brought the seeds of many pesky weeds. As stowaways, they brought rats, mice and injurious insects.

The colonists found a continent teeming with a great abundance and variety of wildlife, including billions of wild pigeons, ducks, geese and turkeys, but they brought their own domesticated kinds, including turkeys which had been introduced into Europe from Mexico by the Spaniards. It is a curious fact that our only domestic animal native to North America is this noble bird.

The Indians had one, the dog, but that was descended from those that accompanied their ancestors when they came here from Asia in prehistoric times. When explorers reached the Great Plains they found Indians riding mustangs, and herds of wild ones, descended from the horses brought by Spanish conquistadors. In Texas they found herds of wild longhorn cattle descended from those brought to Mexico in 1521.

Domesticated animals and plants can be controlled because they require man-made conditions and careful tending. But when a wild species is introduced into an area where it never lived before, there is no telling what may happen: either it will multiply and spread like wildfire or it will soon disappear. If it spreads, it may prey upon some native species, or crowd it out, or interbreed with them, or infect it with serious new diseases and parasites. These things happened when people began to import foreign kinds of wildlife.

The nightingale and the skylark disappeared because the English sparrow, brought here in the 1850's to control insect pests, spread so fast that by 1875 it had crossed the continent. Similarly, the starling has increased enormously and become a pest since 1890 when 60 of them were released in Central Park, New York. Carp, introduced as a food fish in the 70's and sold for $80 per pair, have become a nuisance in streams and lakes all over the country.

Since our Gulf coast swamps were stocked with the Coypu or Nutria, a large aquatic rodent from South America, the more valuable muskrats are decreasing. On the other hand, when muskrats were introduced into California, England and Europe they became serious pests because they burrowed into earth dams and canal banks. The mongoose, brought to Hawaii and the West Indies for controlling rats, has played havoc with ground-nesting birds on those islands. Now, in some states, sportsmen are insisting that the large European or San Jua rabbit be imported to improve hunting, in spite of the fact that large parts of Australia were devastated by enormous numbers of this animal.

It is true that the ringneck pheasant furnishes sport for hunters in midwestern states where bobwhite quail and prairie chicken have become scarce. So does the Hungarian partridge in some places. Therefore, in areas where our native grouse are scarce, sportsmen want to bring in European grouse. Others suggest European or Asiatic deer for our western grasslands. Rather than introduce new species of wildlife, we should spend more thought and money on restoring habitats for native species.

What is our America to be -- a zoological garden?

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