Illinois Poisonous Snakes
We live in Central Illinois. Our home is by some wooded
acres and a pond and a creek. We see several snakes but don't know what
they are called or if they are venomous.
What are the names of the snakes we should avoid and what are their colorings?
Wasn't there a rhyme to help people know what snakes to avoid? Black and
yellow bad for fellow, red and black good for Jack? Is this accurate?
NO EASY ANSWER! There are no coral snakes native to Illinois, those are the
ones the rhyme is about. The Peterson Field Guide to Reptiles and Amphibians
is a good identification guide easily available, and includes range maps
that will tell you which ones are likely to be found in your area. For much
more detail the Illinois Natural History Survey publishes an excellent
detailed book on Illinois herps. You can get a great deal of information on
their publications and much else from their web site.
our rhyme isn't bad as far as it goes. It will let you know the
difference between a coral snake (very venomous) and a king snake (a
non-venomous snake known for eating other snakes, including venomous ones.
However, your rhyme doesn't identify all poisonous snakes. Fortunately for
identification, all venomous snakes in North America other than the coral
snake are pit vipers, which have some characteristics in common. All have
shallow pits on the sides of their heads which are heat-sensing organs, and
all have vertically-oriented slitlike pupils. The poisonous snakes you
would be most likely to encounter where you are are copperheads and
cottonmouths (water moccasins), though rattlesnakes are found in all fifty
You can find informationon snakes in North America at
http://www.pitt.edu/~mcs2/herp/SoNA.html. A site of snakes on Indiana
(there's no difference between Illinois and Indiana once you leave Chicago,
right?) is at
Richard Barrans Jr., Ph.D.
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Update: June 2012