When you think of snake misidentification
you tend to think about the confusion between Coral Snakes and Scarlet and Scarlet King Snakes.
However, the most common snake misidentification that occurs is
between the Water Moccasin (Cottonmouth) and virtually any snake
found in or near the water. The purpose of this article is to help
you identify what is and what is not a Water Moccasin. A secondary
aim is to dispel some of the myths of Water Moccasin behavior.
The Water Moccasin is a dangerously venomous snake found
through most of the Coastal Plains, ranging as far north as Virginia.
As it's name implies, it is a snake that lives in and around water.
There are two subspecies that occur in the Coastal Plains, both are
similar in outward appearance and their differences are irrelevant to
this article. Aside from the Water Moccasin there are many other
aquatic or semi-aquatic snakes in the Coastal Plains, none of which
are dangerous. The fact is that there are over 20 varieties of snake
in the Coastal Plains that make a living around the water and only
one is the Water Moccasin. Many of these snakes have similarities,
though, it really doesn't seem to matter how DIS-similar
they are to the Water Moccasin because the only criteria that seems
to make any difference to the lay-observer is that fact that the
snake was near the water.
When observing snakes near aquatic
habitats, they may or may not be Water Moccasins. That being said, it
is a conceeded fact that Water Mocasins are very common. However,
several of the other species that share its habitat are just as or
more common. Be that as it may, some of the snakes observed will be
Water Moccasins, so the observer should be careful. Always stick to
the principle of not approaching any unfamiliar animal. The snake
will not approach you, so your decision will directly determine the
dangerousness of the encounter. It is often rumored that Water
Moccasins are extremely aggressive and will chase a humans that comes
too near. That complete hogwash.
Water Moccasins are
large-looking snakes. A 30 inch Water Moccasin will look
larger than it really is because of its girth. In fact,
snakes over 36 inches are uncommon, but eye-witness
accounts of them abound. All of the other aquatic snakes
(I will group them all under the term "aquatic snakes"
even though this is a coarse description) are more
slender, though some species of water snake such as the Brown Water
Snake (Nerodia taxispilota) can be fairly
hefty at large size. Even so, a 36 inch Water Moccasin
will be a thicker animal than even a 5 foot water snake.
A Water Moccasin seen from a distance away will look like
a big snake.
Water Moccasins behave
differently than other aquatic snakes. All will flee
given the opportunity, but Water Moccasins will only flee
if they sense that they can reasonably get away.
A 30 inch Water Moccasin on a swamp road in SC
Photo by Gerry Salmon
A Water Moccasin displays its mouth and fangs
Photo by W.T.Helfrich
If the water is close, then
they will often dive for it, even if the threat is
between them and escape. I have had them rush around me
and over my feet to get to the water. This may be a
source of some of the Water Moccasin's rumored (but
non-existent) aggressiveness. Most other aquatic
snakes will usually flee away from the threat even if it
drives them away from the water.
However, if a Water Moccasin is
caught out in the open, it will coil and display by
opening its mouth wide exposing the white liningof its
mouth (hence its second name cottonmouth).
I believe that this behavior serves two purposes, as a
threat and as a practical defense of its head. It would
certainly be difficult to grab this animal by the head
without being bitten.
Be advised, though the Water
Moccasin is not aggressive, it will readily bite and
bite from a Water Moccasin can be very serious. Their venom is
very destructive to the tissue around the bite and bite
victims often get nasty bacteriological infections like
A swimming Water Moccasin in SC
Photos by Gerry Salmon
If you look at the pictures above,
you can see that the Water Moccasin is extremely buoyant. Most
of it's body is above the surface. This is a trait of all Pit Vipers.
Below are pictures of a Banded Water Snake
swimming along a bank. Notice that its body is mostly submerged
with only an occasional coil breaking the surface. This is
typical of all non-venomous snakes in the coastal plains. Also
note how much more slender the water snake is than the Water
Moccasin. This snake is of similar length to the Moccasin in
the pictures above.
Swimming Water Snake in Currituck
Photo by Scott Matthew Quint
| It is often Difficult to
distinguish the Water Moccasin from the various water snakes,
especially when the snakes are dry as most are not brightly
colored. Always mind the simple rule of not approaching any snake
when you are not absolutely sure of its identification.
However if you are concerned about snakes in and around your home
or favorite fishing hole, look for the distinguishing
characteristics described here.