General Stuff About Snakes

Snakes are descended from lizards and at some point in their evolution had legs. Some of the more "primitive" species still retain vestigal hind limbs, which appear as tiny spurs. Legless lizards can be distinguished from true snakes by the presence of ears and moveable eyelids. True snakes have special transparent scales called "spectacles" covering the eyes. These do not move, so snakes cannot blink. It is this steady stare which is largely responsible for the myth that snakes are hypnotic. True snakes also lack not only external ears, but internal auditory organs as well. They are quite deaf to airborn sounds, but they are remarkably sensitive to ground vibrations. Snakes which seem to be charmed by music are actually responding to the movement of the charmer.

The broadest and most obvious way to categorize snakes is into venomous and non-venomous groups. The terms venomous and poisonous are essentially interchangeable. Only four snake species which occur naturally in Illinois are venomous. They are Cottonmouth, Copperhead, Timber Rattlesnake, and Eastern Massasauga (a type of rattlesnake). They are all members of a group referred to as pit vipers which have special pits between the nostril and eye on each side of their head. These pits are able to detect minute variations in temperature such as those of warm-blooded prey. All four are detailed individually under Venomous Illinois Snakes elsewhere in this feature. Non-venomous species far outnumber the venomous species in Illinois. These are colubrid snakes ranging from small brown snakes and flathead snakes less than 8 inches long to the Bullsnake which rarely exceeds 7 feet in length. Even the Bullsnake presents no serious danger to man, though bites can be quite painful and should always receive medical care. Among the most common Illinois snakes are the Common Gartersnake (often miscalled a Garden Snake), the black Ratsnake, and the black Common Kingsnake. These snakes have much more to fear from man than man has to fear from them. Gartersnakes are often found in low grass or gardened areas. Their diet is mainly earthworms and frogs. They are fairly quick snakes and will flee if allowed to do so. A bite from the largest gartersnake in the state will probably produce little more than a scratch. The black ratsnake's diet consists almost entirely, as it's name suggests, of rats and mice. A large ratsnake can consume nearly 10 pounds of rodents each year, which makes them a valuable asset to farmers and others. The best snake for those who dislike them is a kingsnake. Kingsnakes are immune to the venom of other snakes and actually seek them as food. If one has a kingsnake nearby, it is unlikely that many other snakes will be.

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