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Western Rat Snake (Pantherophis obsoletus)
DescriptionThis species was previously known as the Black Rat Snake (Elaphe obsoleta obsoleta). Adults of this species in Arkansas are large, muscular, constricting snakes. The dominating dorsal coloration is black. The chin and throat has a decidedly lighter coloration, usually a cream or white. The ventral coloration varies greatly from white to salmon to dark gray; a checkerboard pattern is typically present. Some amount of juvenile patterning may be retained well into adulthood, showing up as flecks of white, salmon, or yellow between the scales. Juveniles of the species look decidedly different from the adults. Complete darkening may take 2-5 years. The juvenile patterning could best be described as "blotched". The background coloration can vary from light gray to brown to tan. The blotches are dark; either black, dark brown, or dark gray. These blotches may be bordered with a thin outline of cream. This species was long considered the same species as the Gray Rat Snake, Texas Rat Snake, Yellow Rat Snake, and Everglades Rat Snake. Recent analysis has suggested the redefinition of this complex into three distinct lineages: Eastern Rat Snake (found east of the Apalachicola River and Appalachian Mountains), Midland Rat Snake (found between the Apalachicola River and the Mississippi River), and Western Rat Snake (found west of the Mississippi River). The Western Rat Snake can be distinguished from the Eastern Racer, the other common "black snake" found in Arkansas, by the presence of a ridge (called a keel) on each body scale. The Western Rat Snake also has a larger head and therefore a more distinct neck than the Eastern Racer. This species is known by several common names, including Black Rat Snake, Chicken Snake, Mountain Black Snake, or Pilot Snake. Often, it is simply Black Snake. HabitatsThis species can be found in a variety of habitats, especially where there is an abundance of mice and rats. Ideal habitat for this species can be found in and around barns, chicken houses, brush piles, old junk piles, and other similar structures. They can be found in both woodlands and open fields. A large portion of their time is likely spent high up in trees, either coiled in hollows or stretched out on branches. This species, due to its larger size and need to actively forage, spends a good portion of time basking. The dark dorsal coloration facilitates absorbing heat from the sun quickly. Favorite "hot" spots are under loose pieces of tin and (to the detriment of the snakes) highway blacktop. Habits and Life HistoryThe snake appears to follow a pattern typical for many species in the state: hibernate through winter, breed in the spring, and lay eggs in the summer. Road kills of Rat Snakes in the early spring often provides the first evidence that snakes have emerged from hibernation. During this time, Rat Snakes are travelling to their summer foraging areas, searching for mates, and basking. Gravid females later in the summer will lay a number of eggs (up to 15 is not unusual). One of the earliest species to emerge in the spring, the Rat Snake is also one of the last in the fall to seek a den site. It is thought that a single den site may be used year after year. The namesake "Pilot Rat Snake" comes from the erroneous belief that a Rat Snake will "pilot" other snakes, including venomous species, to their den site. Despite this misnomer, it is true that Rat Snakes may select the same hibernacula as other snakes due to the favorability of the temperature and structure provided. Rat Snakes may also hibernate singly in tree hollows, root structures, or animal burrows. Prey and Hunting TechniquesThis species eats a variety of warm-blooded prey, not just rats as the name implies. Any mammal or bird that is slow enough to catch and small enough to eat is fair game. Bird eggs are also a favorite. While this species usually hunts by actively seeking after prey, it is also opportunistic and is certain to seize upon any suitable prey that wonders by it. A Rat Snake is a powerful constrictor that wraps its body around prey with lightning speed. Once a mouse or other rodent is clenched in a Rat Snake's coils, there is little question as to the outcome. Temperament and DefenseThe temperament of Rat Snakes varies by individual, though most tame with some handling. As defense, a Rat Snake will employ the usual: pooping, releasing a foul-smelling musk, and biting. When defensive, they may tense their coils around a handler's hand and become reluctant to let go until positioned low to the ground so that they can "crawl out of their grip". ConservationDespite an apparent bad track record with regard to human encounters, this species remains abundant and common. Most human-attributable deaths are caused by vehicles. The species has a true affinity for blacktop, but its large size, coupled with high-speed traffic, and unfavorable attitudes makes for a deadly mix. Farmers who raise chickens may consider the Rat Snake to be a true pest (since nothing is tastier for a Rat Snake than baby chickens and chicken eggs). The myth of Rat Snakes interbreeding with Copperheads to produce venomous hybrids is occasionally used as reason for killing these "disguised killers", however, such myths are completely untrue and unfounded. State Distribution and Abundance
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