Nature Bulletin No. 270-A   May 20, 1967
Forest Preserve District of Cook County
Richard B. Ogilvie, President
Roland F. Eisenbeis, Supt. of Conservation

****:COMMON SNAKES

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 
harmless.

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!