Fort Leonard Wood is home to many unique species of wildlife, including some species that can be dangerous, such as venomous snakes.

The Fort Leonard Wood Directorate of Public Works, Environmental Division, Natural Resources Branch, manages and maintains records of all wildlife species on the installation and maintains records of 41 species of reptiles, including eight lizards, 11 turtles, and 26 species of snakes.

Missouri has five species of venomous snakes, all in the viper family: the Osage copperhead, Western cottonmouth (also known as water moccasin), Timber rattlesnake, Massasauga rattlesnake and Western pygmy rattlesnake.

These vipers have pits on the sides of their heads that can detect heat from mammalian prey, such as mice, and of course the notorious fangs, which are hollow delivery devices that can channel and inject venom. The venom assists these species in immobilizing their prey but also acts as a potent, and sometimes deadly, defensive mechanism when they bite.

Only two of those venomous species are recorded on Fort Leonard Wood: the Osage copperhead and the cottonmouth.

The Western pygmy rattlesnake occurs just to the south of the Fort Leonard Wood area. The timber rattlesnake -- the most widespread of all the rattlesnakes in the eastern United States -- occurs regionally but has not been officially recorded within the boundary of Fort Leonard Wood. The Massasauga rattlesnake prefers the specific habitats of large moist prairie and wetland areas in northern Missouri.

Active in autumn
Reptiles, including snakes, are ectothermic, and they must absorb heat energy directly from the sun or from their environment to maintain optimum body temperatures.

Many species will bask in the sun or absorb latent heat through elements in their environment that hold heat, such as rocks and other hard surfaces. That is why aquatic turtles lay on logs and why snakes sometimes come out on sidewalks and trails in the evenings -- especially this time of year, as nights begin to get cooler and snakes are still active but must work to regulate their body temperatures.
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A cottonmouth takes a defensive posture on Fort Leonard Wood. Both copperheads and cottonmouths are venomous snakes that are native to Missouri and common on Fort Leonard Wood.

Snakes in temperate regions like Missouri become inactive during the winter. They tend to be most active in early summer and again this time of year, in early autumn, especially after rains.

So, be mindful of snakes that can be just about anywhere on Fort Leonard Wood, even in cantonment areas.

Look for colors, patterns
Sometimes snake species are misidentified, as there are quite a variety of colors and patterns of snakes on Fort Leonard Wood, and some change looks as they change from juveniles to adults.

Copperheads have a distinctive hourglass brown-tan-white pattern, and cottonmouths vary from brightly bronze, or coppery, to nearly black. Both of these species tend to be primarily nocturnal, but as temperatures cool, can be observed basking more often during daylight hours.

Other species that sometimes are misidentified as venomous from Fort Leonard Wood include water snakes, rat snakes, hognose snakes, racers, coachwhips and kingsnakes.

Both prairie and speckled king snakes are immune to the venom from copperheads and cottonmouths and, being fast-acting powerful constrictors, can actually prey on these venomous snakes.

Only rattlesnakes have the distinctive rattles at the tips of their tails and new segments are added as the snake grows and sheds its skin.

Many snakes "rattle" their tail when disturbed, and if it happens to be in next to dry leaves or something else with which a sound can resonate, a rattle noise may be audible.

With rattlesnakes and other snakes that exhibit this behavior it is a general warning that means, "You are too close to me now. Back off!"

Both the cottonmouth and the copperhead are closely related (genus: Agkistodon) and have broad triangular heads with venom sacs behind the pits and also have distinctive vertical pupils. If you are close enough to see that, you are likely too close for comfort.

Cottonmouths also have the notorious habit of flashing open their white mouths at close encounters -- if you see that, back away, slowly, if possible, and leave the area. The snake is demanding respect and more personal space at -- and that point, they deserve it.

(Editor's note: Article provided by Kenton Lohraff, a wildlife biologist with the Fort Leonard Wood Natural Resources Branch.)