About Coluber constrictor Linnaeus, 1758
Adult eastern racers (Coluber constrictor) typically reach a total length (including the tail) of 50 to 152 cm (20 to 60 in), varying by subspecies. The largest recorded specimen had a total length of 185.4 cm (73.0 in). The average adult weighs around 556 g (1.226 lb), and there is almost no difference in size between males and females. Color patterns vary widely across subspecies. As their common names suggest, most are solid-colored, with common variants named black racers, brown racers, tan racers, blue racers, or green racers. The term "runner" is sometimes used in place of "racer" in these common names. All subspecies have a lighter underbelly that is white, light tan, or yellow. Juveniles have more prominent patterning: a central row of dark blotches runs down the back on a lighter base color, with no patterning on the tail. As they age, the back darkens, and the juvenile pattern fades away gradually. Coluber constrictor is found across most of the United States, on both sides of the Rocky Mountains. Its range also extends north into Canada, and south into Mexico, Guatemala, and Belize. This species is often found near water, but also occurs in brush areas, trash piles, roadsides, swamps, and suburban areas. It is the most common snake found in residential neighborhoods in Florida. Eastern racers spend most of their time on the ground, but are skilled tree climbers. They can be found in shrubs and trees raiding bird nests for eggs and chicks, and also hunt small adult birds including finches, canaries, and thrashers. Most eastern racers prefer open, grassland-type habitats, where their sharp eyesight and speed give them an advantage. However, they are also found in open forest and even semiarid regions. They are usually found not far from covered areas they can use for hiding. Mating for Coluber constrictor occurs in spring, from April to early June. Around one month after mating, the female lays between three and 30 eggs in a hidden nest site, such as a hollow log, an abandoned rodent burrow, or under a rock. Juveniles hatch in early fall. Newborns measure 20–26 cm (8–10 in) in total length. Eastern racers reach sexual maturity at around 2 years of age. This species is known to lay eggs in communal nesting sites, where multiple snakes — even snakes of other species — all lay their eggs together.
