| Few
poisonous snake species occur in North America, and they are all easy to identify as
venomous. Several non-venomous snakes mimic the venomous ones. The venomous ones
fall into two groups: 
Eastern Coral Snake, Micrurus
fulvius (DANGEROUS: DON'T YOU HOLD
ONE!)
- The Coral Snakes, of which there
are 2 species, one of them shown above. Red in the map below shows the approximate
distributions of both species, the Eastern Coral Snake living from Texas to North
Carolina and the Arizona Coral Snake in southern Arizona and extreme southwestern New
Mexico. Therefore, most North American backyards, even if they adjoin a wilderness area,
will never harbor a coral snake. Coral snakes are easy to identify, with boldly colored,
broad, alternating bands (not long lines) of red, yellow and black.
A number of harmless snake species also have broad alternating bands of these
colors, but the coral snake's colored bands are arranged in a unique sequence, which you
can remember with this poem: Red on yellow/ Will kill a
fellow. Thus the red bands are always framed with yellow bands. Most
but not all harmless look-alike snakes have their red bands framed with black. Sometimes
the yellow bands are almost white.
- The Pit Vipers -- 17 species in
all -- include rattlesnakes, copperheads, and water moccasins,
found throughout most of the U.S. All members of the pit viper family share two
characteristics that separate them from all other clobbered snakes (boas and pythons can
also have these features):

- As the copperhead photo at the right shows, they have cat-eyes
-- the black pupil is shaped like the cross section of a vertically positioned
convex lens.
- There's a pit, or hole, between the snake's eyes and
its nostrils (thus the name pit viper). This pit is heat-sensitive, enabling the snake to
locate warm-blooded prey in total darkness. This is also clearly visible in the above
picture, between the bottom of the eye and the bottom of the nostril. See it?
Of course, if you live within easy walking distance of a more
or less natural area where pit vipers are known to occur, you won't want to approach any
unknown living snake to see if its pupils are convex and if it bears heat-sensitive pits.
To identify venomous snakes from beyond striking distance you must study pictures of the
poisonous species in your area and commit the details of their appearances to
memory. There is no short-cut. Pit vipers do tend to have more or less heart-shaped
heads because of the bulging poison glands behind their eyes. However, many harmless
snakes also have more or less heart-shaped heads. |