how to identify Snakes

 
Complete list of species, with images and family descriptions.  Click on web address for Snakes of  North America

Identification of Poisonous Snakes

Because all poisonous snakes are members of the pit viper family, you can easily tell the difference between poisonous and harmless snakes. The three ways to distinguish poisonous snakes: Pupil shape. The black part in the center of the eye (pupil) of harmless snakes is round. Poisonous snakes have egg-shaped or cat-like (elliptical) pupils (Figure 2a). In good light, you can easily see the pupil shape from a safe distance because snakes cannot jump nor can they strike from more than one-third of their body length.

Pit. Poisonous snakes also have a very conspicuous sensory area or pit (hence the name “pit viper”) on each side of the head. The pit looks somewhat like a nostril and helps the snake locate warm-bodied food. It is located about midway and slightly below the eye and nostril (Figure 2a). Harmless snakes do not have pits. Scale arrangement. The underside scales of a venomous snake’s tail go all the way across in a single row from the anal plate (Figure 2b). The very tip of the tail may have two scale rows. Nonpoisonous snakes have two rows of scales from the vent to the end of the tail. This characteristic can also be observed on skins that have been shed. Other features that may help you identify a poisonous snake at a distance: Head shape. Venomous snakes usually have a triangular (wide at the back and attached to a narrow neck) or “spade-shaped” head. Be aware that many harmless snakes flatten their heads when threatened and may appear poisonous. Distinctive sound. Rattlesnakes will usually sound a warning rattle (a buzz or a dry, whirring sound) when approached. However, many nonpoisonous snakes (black racers, corn snakes, rat snakes, milk snakes, and pine snakes) and several poisonous snakes (copperhead and cottonmouth) often vibrate their tails when threatened. The sound produced by this vibration often imitates a rattle or hissing sound when the snake is sitting in dry grass or leaves. Tail. You can easily recognize young cottonmouths and copperheads by their bright yellow or greenish yellow tail.

Identification of Poisonous Snakes

Because all poisonous snakes are members of the pit viper family, you can easily tell the difference between poisonous and harmless snakes. The three ways to distinguish poisonous snakes: Pupil shape. The black part in the center of the eye (pupil) of harmless snakes is round. Poisonous snakes have egg-shaped or cat-like (elliptical) pupils (Figure 2a). In good light, you can easily see the pupil shape from a safe distance because snakes cannot jump nor can they strike from more than one-third of their body length.

Pit. Poisonous snakes also have a very conspicuous sensory area or pit (hence the name “pit viper”) on each side of the head. The pit looks somewhat like a nostril and helps the snake locate warm-bodied food. It is located about midway and slightly below the eye and nostril (Figure 2a). Harmless snakes do not have pits. Scale arrangement. The underside scales of a venomous snake’s tail go all the way across in a single row from the anal plate (Figure 2b). The very tip of the tail may have two scale rows. Nonpoisonous snakes have two rows of scales from the vent to the end of the tail. This characteristic can also be observed on skins that have been shed. Other features that may help you identify a poisonous snake at a distance: Head shape. Venomous snakes usually have a triangular (wide at the back and attached to a narrow neck) or “spade-shaped” head. Be aware that many harmless snakes flatten their heads when threatened and may appear poisonous. Distinctive sound. Rattlesnakes will usually sound a warning rattle (a buzz or a dry, whirring sound) when approached. However, many nonpoisonous snakes (black racers, corn snakes, rat snakes, milk snakes, and pine snakes) and several poisonous snakes (copperhead and cottonmouth) often vibrate their tails when threatened. The sound produced by this vibration often imitates a rattle or hissing sound when the snake is sitting in dry grass or leaves. Tail. You can easily recognize young cottonmouths and copperheads by their bright yellow or greenish yellow tail.

There’s a reason that knowledge is power. Knowing which snakes in Alabama and nationwide, are potential threats and which are not makes all the difference in your ability to handle them and keep calm when they’re around. At Cahaba Snake Trap™, we offer information about snakes in addition to the products you need to catch them. Here we detail how to identify venomous species. More info is provided in our FAQ page. Because nearly all of the dangerous types are members of the pit viper family, you can easily tell them apart from the safe ones. The 3 characteristics to look for are the:

  • Pupil shape
  • Pit
  • Scale arrangement

For harmless varieties, the pupil, or the black part in the middle of the eye, is round. Venomous species have egg-shaped, or cat-like, elliptical pupils. In good lighting, you can easily see the pupil shape from a safe distance because snakes cannot jump or strike from more than a third of their body length.

Tips From Our Snake Identifier

Aside from the pupil, one of the key factors to study in a snake is its pit. Poisonous species possess a conspicuous sensory area or pit, hence the name “pit viper”, on both sides of the head. This pit resembles a nostril and helps the snake locate warm-bodied food. You’ll find it midway and slightly below the eye and nostril. Harmless snakes don’t have these pits, so if you don’t see it, you know you can breathe easy.

The other giveaway is the scale arrangement. The underside scales of a venomous snake’s tail extend all the way across in one row from the anal plate. At its tip, the tail may have 2 scale rows. Harmless snakes have 2 rows of scales from the vent to the end of the tail. This is also seen in shed skins.

How To Identify From a Distance

In some cases you may not be able to get close enough to a snake to see the pit or pupil. Other features that may help you in these situations include head shape and distinctive sounds. Venomous snakes usually have a triangular or “spade-shaped” head that’s wide at the back and attached to a narrow neck. However, bear in mind that many harmless snakes flatten their heads when threatened and may appear poisonous when they aren’t.

Rattlesnakes will usually sound a warning rattle, which sounds like a buzz or a dry, whirring sound when approached. Unfortunately, a vibrating tail may not prove the species for sure. Many safe snake varieties like black racers, copperheads, and cottonmouths as well as corn, rat, milk, and pine snakes vibrate their tails when threatened. This vibration often imitates a rattle or hissing sound when the creature is sitting in dry grass or leaves, so it’s easy to mistake it for a rattlesnake. The good news is that young cottonmouths and copperheads are easily recognizable by their bright yellow or greenish yellow tail.

 

The best way to learn snake identification is by contacting our professionals. We’re honored to help keep you and your family safe. We are based in Alabama and serving nationwide.