Gray ratsnakes are large nonvenomous snakes native to North America. In the southern part of their range these snakes retain the juvenile pattern of dark elongate dorsal blotches separated by four, or more, pale gray body scales, a light gray crown with dark striping that forms an anteriorly facing spearpoint, and a solid band which covers the eyes and extends rearward to the posterior upper labial scales. However, in the northern part of their range, Gray ratsnakes are black in adulthood. The venter is usually off-white or pale gray with darker irregular blotches. The dorsal scale rows around midbody are usually weakly keeled.
Gray ratsnakes are found in the eastern and central United States. They occur relatively continuously throughout the major part of the eastern half of the United States, along the western edge of the Appalachian Mountains, from southwestern New England to the Gulf of Mexico, westward to the Mississippi River, and northward from northern Louisiana to southwestern Wisconsin. In Canada, these snakes occur in two disjunct regions of southern Ontario: the Carolinian forest region along the north shore of Lake Erie in the southwest, and the Great Lakes/St. Lawrence region in the southeast. Gray ratsnakes live in many types of hardwood forests and cypress stands, along tree-lined streams and fields, and even around barns and sheds in close proximity to people.
Gray ratsnakes are mainly terrestrial but they are also agile climbers. They are active during the day and may become nocturnal in summer. Gray ratsnakes are generally solitary creatures but may hibernate communally usually in rocky outcrops or underground. When startled, these snakes stop and remain motionless with their body held in a series of wave-like kinks. They will also rattle their tail against whatever it is lying on, making an audible buzzing sound. Gray ratsnakes will defend themselves by raising their head and bluffing a strike. If handled, they will musk a victim by releasing the foul-smelling musk of their cloaca and will bite if necessary. However, Gray ratsnakes are less likely to bite than other members of its genus.
Gray ratsnakes are carnivores and feed primarily on small mammals, birds, and bird eggs. Neonates and juveniles prefer to hunt frogs and lizards.
The breeding season of Gray ratsnakes usually lasts from April to July and females lay 5 to 27 eggs around mid-summer. Eggs are laid in rotting logs, stumps or under rocks. Hatchlings usually emerge in September. They are fully developed at birth and measure 25-30 cm (9.8-11.8 in). Young females are known to become reproductively mature when they are 7-9 years old.
The main threats to Gray ratsnakes include habitat destruction due to agricultural development and urbanization. These snakes are also often killed because of fear. Road mortality is another major reason for population decline.
According to IUCN, the Gray ratsnake is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List.