NORTH AMERICAN SNAKEBITES
a. With the exception of a few species not found in North America, snakes tend
to be shy or passive by nature. Usually, they will avoid contact with human beings
unless they are injured, trapped, or disturbed. However, both poisonous and
nonpoisonous snakes show some aggressiveness during breeding season.
b. All species of snakes can swim. Many snakes can even remain underwater
for long periods without drowning. They can also bite while they are in the water. The
bite of a poisonous snake sustained in water is just as dangerous as one sustained on
c. Many snakebites can be prevented by avoiding areas where snakes like to
rest (next to logs, in heavy brush, on rocky ledges, and so forth). When practical, clear
the area of dense undergrowth, trash, and piles of rocks or logs that may attract snakes.
d. Often, the thought of a snakebite creates fear and confusion because the
individuals involved fear the worst. Reassuring the casualty and reducing his anxiety
are important steps in rendering treatment. Even if a person is bitten by a poisonous
snake, the snake may have injected little or no venom (poison) into the casualty if the
snake has recently struck an animal and temporarily exhausted its supply of venom.
IDENTIFY POISONOUS NORTH AMERICAN SNAKES
There are four kinds of poisonous snakes native to North America. They are the
rattlesnake, copperhead, water moccasin, and coral snake.
a. Pit Vipers. The rattlesnake, copperhead, and water moccasin are pit vipers.
Pit vipers are poisonous snakes that have a deep pit between the eye and nostril on
both sides of the head. The pit contains a sensory organ for detecting the body heat
from the snake's prey. Pit vipers have thick bodies, thin necks, and flat, triangular
heads that are very distinct from their bodies. Their eyes are elliptical and their pupils
are vertical (like the pupils of a cat). A pit viper also has two large, hollow fangs that
inject venom into its victim. The venom will kill small animals. The venom also contains
strong enzymes that help the snake to digest its prey.
(1) Rattlesnakes. Rattlesnakes (figure 1-1) are found in every state of the
continental United States (CONUS). They can be found in the desert, grassy plains, forests, and rocky
Fully-grown rattlesnakes range from three to eight feet in length and can be identified by
the rattles at the end of their tail. Often, a rattlesnake will shake his tail and make a
rattling sound (caused by layers of incompletely shed skin at the end of his tail) before
he strikes in an attempt to scare the intruder away.