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Photo by Suzanne L. Collins

Common Name: Cottonmouth

Scientific Name: Agkistrodon piscivorous


Size: Length in Kansas up to 36 inches


Kansas range map for the Cottonmouth

Range: Natural range restricted to the Spring River drainage in eastern Cherokee County in extreme southeastern Kansas. A number of these snakes were deliberately released in the Verdigris River in Montgomery County in the mid-1970s; these snakes may no longer exist there today.

Description: It is a misconception that this species occurs broadly across the state. It is commonly confused with several species of non-venomous water snakes of the genus Nerodia. The only records for this species in Kansas are from the Spring River drainage in extreme southeastern Kansas.  Uniformly dark gray or black with no rattle on its tail and a small pit on each side of its head between and slightly below the eye and nostril; indistinct bands are present on the back and sides but normally can be seen only when the snake is submerged in water. Belly is dark. Young adults may be banded. Young are banded like juvenile Copperheads; yellowish or greenish tails.

Habits: During spring and fall, active along small streams and backwaters. In summer, becomes nocturnal and prowl oxbows and other stillwater habitats. During the fall, leaves aquatic situations and travels to upland den. Two to 15 young per litter are born in August and September. Eats insects, fishes, salamanders, frogs, turtles, lizards, other snakes, birds and small mammals.

Basic Information About Snakebites

Death from snakebite is rare. There is only one documented fatality in Kansas since 1950. Snakebites still occur and knowing what to do is important for anyone who spends time in areas where venomous snakes are found.

Precautions: Always wear protective clothing when hiking the rugged areas of Kansas and never go alone. Wear gloves if possible and don’t stick your hands under rock ledges, logs or stumps. Sturdy, high boots are preferred footwear. Stay on paths or trails and watch where you walk. If you discover a venomous snake, don’t try to catch or harass it. Venomous snakes are a fascinating part of our environment. They are easy to observe and make easy subjects to photograph with an appropriate lens. Be familiar with the venomous snakes of Kansas. Learn to recognize the harmless snakes that resemble potentially dangerous ones. For example, Northern Water Snakes frequently are mistaken for Copperheads and Cottonmouths.

If you are bitten by a snake:  Was the snake venomous? If you know you have been bitten by a harmless snake, it will save you much stress and eliminate the need for treatment. Many people are bitten by harmless snakes each year and experience nothing but small scratches that readily heal. If you are certain a venomous snake was involved, get to the nearest hospital or medical facility as quickly as possible. If possible, notify them ahead of time via telephone of your situation. This gives the physician time to prepare and call the nearest poison information center for advice.

The Arizona Poison and Drug Information Center in Tucson (1-800-222-1222) maintains a list of which types of antivenins (sometimes called antivenoms) are available and can advise a physician where to call in the event of a bite from a venomous snake.

If bitten by a venomous snake:

  • Stay calm.
  • Treat for shock.
  • Drive to the nearest hospital or medical facility.
  • Do not attempt to kill or capture the snake. It gives the snake another opportunity to bite.
  • Do not use a tourniquet. If tied too tight, it may cause the loss of a limb.
  • Do not make cuts through or near the site of the bite.
  • Do not try to suck venom from the site of the bite. You might have a tooth cavity or gum sore and this would place venom into that wound.
  • Do not allow anyone, including a physician, to administer antivenin to you UNLESS you have FIRST been tested to determine whether or not you are allergic to antivenin.

Regional Poison Information Centers are also important sources of information.

Kansas Poison Control:

Mid-America Poison Control Center

24-hour Emergency Hotline: 1-(800) 222-1222


Not in Kansas?

Find your state poison control center here.