The Eastern racer ( Coluber constrictor) is a nonvenomous snake species endemic to North America and Central America. Known for its exceptional speed and agility, the Eastern racer is aptly named as one of the fastest snakes in North America, capable of moving up to 6 km/h (4 mph). This widely distributed species is found predominantly in the eastern United States. While the species name constrictor might suggest constriction, these snakes actually overpower their prey with speed and swallow it whole. This article delves into the dietary habits of this fascinating reptile, exploring its diverse prey and hunting strategies.
Physical Characteristics and Identification
A relatively large, slender snake reaching up to 152 cm (60 in), the Eastern racer exhibits considerable variation in appearance across its eleven subspecies. Adults are uniformly black with smooth scales, large eyes, and often a white chin. The venter is dark gray to black. Dorsally and laterally it may be bluish to gray or greenish. Ventral color varies from cream to bright yellow. They may be confused with other large black snakes such as Rat Snakes, Kingsnakes, Coachwhips, or dark Hognose Snakes, but Racers are more slender, lack keeled scales, and do not have the upturned snout of hognose snakes. Behavior is often diagnostic: while rat snakes, kingsnakes, and hognose snakes tend to freeze when approached, racers usually flee quickly or may strike defensively. Juveniles look entirely different, being tan or gray with reddish-brown blotches down the back. Young of this species have a pattern of large, light-edged blotches on the back alternating with smaller spots on the sides. This pattern is distinct on the front half of the body and fades toward the rear. Young specimens also have scattered dark speckles on the belly. As they grow older, young North American Racers lose all pattern and attain the uniform appearance of adults. The tail is unpatterned.
Habitat and Distribution
Eastern racers are found throughout the United States, east of the Rocky Mountains, but they also range north into Canada and south into Mexico, Guatemala, and Belize. In the Southeast, Black Racers occur statewide in Georgia and South Carolina and are among the most common snakes in nearly all habitats. These snakes usually live near water, but also in the brush, deserts, prairies, sandhills, trash piles, roadsides, and swamps, and in suburbia; they are very common in residential neighborhoods in Florida. Most of Eastern racers prefer open, grassland-type habitats where their keen eyesight and speed can be readily used, but they are also found in light forest and even semiarid regions.
Hunting and Feeding Behavior
Eastern racers are carnivores with a broad diet that varies depending on their age and the availability of prey in their habitat. These are fast-moving, highly active, diurnal snakes. They spend most of their time on the ground but are also good tree climbers. These snakes may be found in shrubs and trees where bird nests can be raided for eggs and chicks, as well as small adult birds such as finches, canaries, and thrashers. They often hunt by “periscoping,” their head held well above the grasses or weeds in which they are searching for their prey of lizards, frogs, baby turtles, small snakes, and the nestlings of ground dwelling birds or mammals. As would befit snakes with such hunting techniques, the eyes are large and vision is acute. The North American Racer relies primarily on sight to capture food. It pursues and eats any small animal that moves.
One of the most striking behaviors of the Eastern racer is its curiosity. It often investigates disturbances in its immediate vicinity by raising the front part of its body off the ground. This behavior not only allows it to survey its surroundings but also to spot potential threats and opportunities from a distance.
Read also: Dietary Habits of Whip-poor-wills
Juvenile Diet
Juveniles feed on invertebrates including crickets and grasshoppers, but also take juvenile lizards.
Adult Diet
Adults feed mostly on vertebrates, including lizards, snakes, and their eggs. According to Fitch (1963, 1982), this snake eats insects, frogs, lizards, other snakes, birds, bird eggs, and small mammals. They probably also eat frogs, mice, and hatchlings of ground-nesting birds when they are available.
Seasonal Activity and Feeding
Eastern racers are generally solitary creatures; they are active from March through October and during winter hibernate communally. These snakes are active normally from April to mid-November, at air temperatures ranging from 60° to 90°F. During spring and fall, they are active at mid-day whereas during summer they can be active during the entire day.
Predators
Predators include birds of prey, mammals, kingsnakes, and larger racers.
Conservation Status
Common and widespread. According to IUCN, the Eastern racer is locally common and widespread throughout its range but no overall population estimate is available.
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