Nature Bulletin No. 270-A May 20, 1967
Forest Preserve District of Cook County
Richard B. Ogilvie, President
Roland F. Eisenbeis, Supt. of Conservation
Most grownups have a dislike or horror of snakes and regard them as
loathsome, or dangerous, or both. Children, however, have a lively
curiosity about snakes. Little tots handle them without fear, and any
prejudices which older boys and girls may have acquired, from their
elders and popular misinformation, can be easily overcome. Actually,
snakes are clean and dry -- not slimy; most of them are harmless; and
many of them are highly beneficial to mankind. There are few kinds of
poisonous snakes -- only four in Illinois -- and, unless in wild isolated
regions, there are none in most localities.
Garter snakes and some of the smaller kinds are frequently found under
boulders or rotting logs or, even in the vacant lots of cities and towns,
flat objects such as lumber, sheets of tin, or roofing material lying on
the ground. The larger snakes are seldom encountered except by
chance. Modern agriculture has greatly reduced their abundance by
drainage of marshes and wet ground, removal of woodlands, and
intensive cultivation which wiped out much of their natural prey. Many
of them are killed by mowers or reapers, and by automobiles on the
highways. Most of these are valuable, especially to the farmer, because
they eat great numbers of mice, rats, ground squirrels, gophers and such
rodents. Several of the smaller kinds prey largely upon insects. Others
eat earthworms, frogs, toads, or fish and aquatic animals, but do little
harm because such creatures are plentiful.
Some snakes, like the bull snake, pilot black snake, fox snake and king
snake, kill their prey by squeezing it and are called "constrictors". The
poisonous snakes kill with their venomous fangs. Others merely seize
the animal in their mouth and gradually swallow it, alive and whole.
Some kinds lay eggs and some give birth to living young. Usually, the
young appear in late summer or early fall.
Of the 32 distinct species of snakes in Illinois, only 18 are found in the
Chicago area and only six of these may be called "common"; abundant
and frequently seen. Three others -- the Smooth Green Snake, the little
brown DeKay's Snake, and its smaller relative, the Red-bellied Snake --
are probably abundant in many places but are seldom seen because they
are so small, so secretive, and so well camouflaged. The Pilot Black
Snake, the Fox Snake and the Bull Snake are all common, all lay eggs,
and are all large. The Common Water Snake, the Queen Water Snake,
the Common Garter Snake, and the Plains Garter Snake are very
abundant, all bear their young alive, and all seize their prey in their
mouths. The Hog-nosed Snake or Puff Adder, the Blue and the Black
Racers, the King Snake, and the Milk Snake or Spotted Adder, are large
egg-laying snakes which are less common. All those named here are
A snake is frequently hard for the ordinary person to identify. An expert
identifies it by the color and markings, by the kind and number of scales
on its back, and by the arrangement of the scales on its belly. Some, like
the green snake and the racers, have a uniform color but the young
racers are spotted and blotched. Some have longitudinal stripes, some
have crossbands, and some have spots or other distinctive patterns.
Their colors tend to darken as they grow older, and the markings
become less distinct, although they are always brighter just after a snake
sheds its skin -- which it does several times during the warm months.
There may also be considerable variation in certain species.
Like a snake's tail, this is the end. Don't hiss!
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Update: June 2012