Bruce Peverley Extension Educator, Agriculture Tulsa County
Species: Forty-six species of snakes are native to Oklahoma. Only seven species are harmful to humans. Venomous species are the copperhead, cottonmouth, and five rattlesnake varieties (the western diamondback, the timber, the prairie, western massasauga and the western pigmy).
Habitat and Distribution: Cottonmouths are aquatic residents of the eastern one-third of the state and those counties along the southern boundary, west to Comanche county. Copperheads can also be aquatic. Cottonmouths, copperheads, massasaugas and pigmy rattlesnakes are usually found in moist areas. Prairie rattlesnakes are found in the prairies of western Oklahoma while the timber rattlers inhabit the forested eastern half of the state. Western diamondbacks are most common in southern and western Oklahoma, but have been found as far north as Tulsa, Cherokee and Adair counties. Rocky outcrops are the favored habitat of rattlesnakes and copperheads. These outcrops provide shelter, basking and possible hibernation sites.
Identification: There are five features that can help you identify poisonous snakes. Presence of rattles on the tail positively identifies a snake as poisonous. Secondly, head shape can help identify poisonous snakes. Poisonous snakes in North American tend to have diamond or triangular shaped heads. Harmless snakes have narrow heads. Thirdly, vertical eye pupils “cat’s eyes” are a strong sign a snake might be poisonous. Fourth, the best identifying character is the facial pit. This is a depression on the side of the face joint below a line between the eyes and the nostrils. The venomous snakes of Oklahoma have facial pits. Fifth, if you have a dead snake a poisonous snake can be identified by examining the scales under the tail. The tail of a snake is the portion of the snake that extends beyond the vent (anus). Poisonous snakes have a single row of scales immediately beyond the vent, while non-poisonous snakes usually have two rows of scales beyond the vent.
Exclusion and Prevention: Snake numbers around homes can be reduced by altering habitat. Simply removing tall grass, brush piles, rubbish, etc. that provides potential cover will reduce snake numbers. Control small mammals, such as mice. Placing feed and grain in rodent proof containers will reduce rodent numbers and thereby reduce snake numbers. Snakes can be kept out of homes by sealing cracks in foundations, around windows, doors and air conditioners. These suggestions will reduce unwanted snakes around your home.