Western Rat Snake
Pantherophis obsoletus
Summary 3
Pantherophis obsoletus – also known as the western rat snake, black rat snake, pilot black snake, or simply black snake – is a nonvenomous species of Colubridae found in central North America. No subspecies are currently recognized. Its color variations include the Texas ratsnake.
Description 4
NOT venomous but may bite if harassed. Head is long and only slightly wider than neck, weakly keeled scales near spine, round pupils. Slender body with a pattern of large dark blotches on a background of lighter tan or gray. Typically 42 to 72 inches (107 to 183cm) in length. (J. R. Dixon and J. E. Werler, Texas Snakes: A Field Guide, University of Texas Press, 2000.)
Behavior 5
When not fully grown, rat snakes are subject to predation by many animals, including other snakes. Once they attain maturity, they are readily preyed on by mammalian carnivores (including the American mink, which weighs no more than an adult rat snake) and large birds of prey (especially red-tailed hawks). When startled, they may freeze and wrinkle themselves into a series of kinks. If they feel further threatened, they may flee quickly or tail vibrate (potentially a form of mimicry, which makes them sound like rattlesnakes). They are also capable of producing a foul-smelling musk, which they will release onto predators if picked up. They spread the musk with their tails in hopes of deterring the threat. When cornered or provoked, black snakes are known to stand their ground and can become aggressive. Counterattacks on large birds of prey, often committed by large snakes in excess of 150 cm (59 in) in length, have resulted in violent prolonged struggles. Utilizing its infamous agility and the great strength of its muscular coils, the black rat snake is sometimes able to overwhelm and kill formidable avian predators such as red-tailed hawks, great horned owls and red-shouldered hawks, though in many cases the bird is able to kill the snake and both combatants may even die.
Common names 5
Other common names include: black chicken snake, black coluber, chicken snake, mountain black snake, mountain pilot snake, pilot, rat snake, rusty black snake, scaly black snake, cow snake, schwartze Schlange, sleepy John, and white-throated racer.
Habitat 5
Rat snakes live in a variety of habitats; some overlap each other. Rat snakes are excellent climbers and spend time in trees. They live in habitats ranging from a rocky hillside to flat farmland.
Preferred habitat 5
It prefers heavily wooded areas and is known for having excellent climbing ability, including the ability to climb the trunk of large mature trees without the aid of branches; the snake is also a competent swimmer. During winter it hibernates in dens, often with copperheads and timber rattlesnakes. This association gave rise to one of its common names, pilot black snake, and the superstition that this nonvenomous species led the venomous ones to the den.
Geographic range 5
Pantherophis obsoletus is found west of the Mississippi River, from eastern and southern Iowa southward through Missouri and Arkansas to western Louisiana, westward to eastern Texas, northward through Oklahoma and eastern Kansas to southeastern Nebraska.
Aside from the usual variety that is black or has patches of black on a lighter background, color variations include
the Texas rat snake, a brown-to-black variant, often with tinges of orange or red, that can be found in southern Oklahoma, Texas, and Louisiana.
Sources and Credits
- (c) Scott Buckel, some rights reserved (CC BY-NC), uploaded by Scott Buckel
- (c) Lee Elliott, some rights reserved (CC BY-NC-SA), uploaded by Lee Elliott
- Adapted by Desmon M Dunn from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Pantherophis_obsoletus
- (c) Amber Leung, some rights reserved (CC BY-SA), https://www.inaturalist.org/guide_taxa/494735
- (c) Wikipedia, some rights reserved (CC BY-SA), https://en.wikipedia.org/wiki/Pantherophis_obsoletus
