|REPTILES OF THE METRO AREA
Northern Copperhead (Agkistrodon contortrix mocasin)
The Copperhead is the only poisonous snake in our area. The pictures here were all taken in
northern Baltimore County. Copperheads are very well camouflaged with the browns and greys of
their back making them almost invisible when sitting in dry leaves. These snakes usually sit very
still when approached and rely on the camouflage to hide them. They feed on small rodents and
birds, which they usually bite and quickly release, then wait for the venom to do its job. After the
prey is dead the snake approaches and proceeds to swallow it. Two pictures on this page show a
copperhead sitting in blueberry bushes which were growing on a large rock ledge. The blueberries
may have attracted birds and small animals which would become food for the snake. This also
could have been a hazard to human berry pickers, although from my experience Copperheads
almost always try to avoid conflict with humans.
The Copperhead was named for the copper-brown color of its head. The back is grey with brown
hourglass shaped markings.
Although these snakes are generally docile, Copperhead bites are the most common venomous
snakebite in the United States. They have a wide range and are very common in parts of their
range, particularly in the southern U.S. Many bites happen when a snake is stepped on either at
night when the snakes are active or when the camouflaged snake is sitting motionless and almost
invisible in dry leaves. A bite from a copperhead is serious, requiring medical care and often
having long-lasting or even permanent physical complications, but deaths are extremely rare even
A component from the venom of the closely related Southern Copperhead (Agkistrodon
contortrix contortrix) has recently been shown to have anti-cancer properties. Contortrostatin is
one of a group of snake venom peptides called disintegrins. Disintegrins isolated from several
snake species bind to the integrins, which are molecules involved in cell adhesion. Contortrostatin
prevents the formation of blood vessels in tumors to block nutrients from the rapidly growing
cancer cells and reduces the routes for the spread, or metastasis, of the cancer through the blood
vessels. Other copperhead venom enzymes and peptides have physiological effects that may be of
medical interest, such as anticoagulants, procoagulants, and blood pressure modulators.
Swenson S, Costa F, Minea R, Sherwin RP, Ernst W, Fujii G, Yang D, Markland FS Jr. -
Intravenous liposomal delivery of the snake venom disintegrin contortrostatin limits breast cancer
progression. - Mol Cancer Ther [ 2004 ] Apr;3(4):499-511
Swenson S, Costa F, Ernst W, Fujii G, Markland FS. - Contortrostatin, a snake venom disintegrin
with anti-angiogenic and anti-tumor activity. - Pathophysiol Haemost Thromb [ 2005 ]
A copperhead on a blueberry bush at Prettyboy Reservoir. The snake was moved from under the bushes to make her more visible.
Three copperheads in what appeared to be a rookery area in Gunpowder Falls State Park. I observed these
snakes for several summers. All appeared to be gravid females, appearing in July and disappearing in late
summer. Unfortunately the snakes were discovered by someone who destroyed the shelter, either to kill or to
catch the snakes.
|A copperhead caught at Prettyboy Reservoir (1976).
|Copperhead at Prettyboy Reservoir (Gravid female, 1979)