Family: Colubridae, Colubrid Snakes view all from this family

Description 34-77" (86.4-195.5 cm). Large, slender, agile, and fast moving. Adults uniformly black, blue, brown, or greenish above; white, yellow, or dark gray below. Young typically gray and conspicuously marked with dark spots on sides and dark gray, brown, or reddish-brown blotches down midline of back. Scales smooth, in 17 rows (15 rows at vent). Anal plate divided.

Subspecies Eleven, poorly defined:
Northern Black (C. c. constrictor), slate black, upper lip scales black, some white on chin, iris of eye brown; s. Maine to e. Ohio south to n. South Carolina, n. Georgia, n. Alabama, and ne. Mississippi.
Buttermilk (C. c. anthicus), black, bluish-black or bluish-green with random white, gray, or yellow spots; extreme s. Arkansas, Louisiana, and adjacent e. Texas.
Tan (C. c. etheridgei), light tan with pale spots; extreme wc. Louisiana into adjacent e. Texas.
Eastern Yellow-bellied (C. c. flaviventris), pale blue, bluish-green, olive-green, gray or brown above, belly cream to bright yellow; e. Montana, w. North Dakota, and Iowa south to extreme n. Arkansas, and the Gulf coast of se. Texas and w. Louisiana.
Blue (C. c. foxii), pale-blue or bluish-green above, belly white or bluish-white; extreme s. Ontario and nw. Ohio west to se. Minnesota, e. Iowa, and Illinois.
Brown-chinned (C. c. helvigularis), slate black, lip scales and chin tan or brown; Apalachicola and Chipola River valleys in Florida panhandle and adjacent Georgia.
Black-masked (C. c. latrunculus), slate gray above, belly pale grayish-blue, black stripe behind eye; se. Louisiana.
Western Yellow-bellied (C. c. mormon), green, olive-green, yellowish-brown or reddish-brown above, belly yellow; s. British Columbia to Baja California east to sw. Montana, w. Wyoming, and w. Colorado.
Mexican (C. c. oaxaca), midline of back green or greenish-gray, sides lighter, belly yellow or greenish-yellow, adults 20-40" (51-102 cm) long; s. Texas and Mexico.
Everglades (C. c. paludicola), bluish-, greenish, or brownish-gray above, belly whitish with pale gray or powder-blue markings, iris of eye usually red; s. Florida Everglades region and Cape Canaveral area of e. Florida.
Southern Black (C. c. priapus), resembles Northern Black, more white on chin, iris of eye usually red or orange; coastal plain from extreme se. North Carolina to Florida Everglades (and lower Florida Keys) west to se. Oklahoma and adjacent Texas; north in Mississippi Valley to s. Illinois and s. Indiana.

Breeding Mates April to late May in most of range; 1-2 months earlier in Deep South. Female lays 5-28 soft leathery eggs with a rough granular texture, 1-1 7/8" (25-48 mm) long, in rotting tree stump, sawdust pile, under rocks or in small mammal tunnel, mid-June to August. Occasionally a number of females deposit their eggs in a communal nest. Young hatch in 6-9 weeks, July to September, are 8-13" (20-33 cm) long. Mature in 2-3 years.

Habitat Abandoned fields, grassland, sparse brushy areas along prairie land, open woodland, mountain meadows, rocky wooded hillsides, grassy-bordered streams, and pine flatwoods; sea level to ca. 7,000' (2,150 m).

Range S. British Columbia and extreme s. Ontario; every state in continental United States, except Alaska; scattered populations through e. Mexico to n. Guatemala.

Discussion Diurnal. May be encountered in most any terrestrial situation except atop high mountains and in hottest desert. Often observed streaking across roads. Although agile and a good climber, it spends most of its time on the ground. When hunting, it holds its head high and moves swiftly through cover. Often hibernates in rocky hillsides in large numbers and with other species. Eats large insects, frogs, lizards, snakes, small rodents, and birds. Despite the scientific name, it is not a constrictor.