NATURAL HISTORY

EASTERN DIAMONDBACK RATTLESNAKE } Crotalus adamanteus
FAMILY: Viperidae

DESCRIPTION: The eastern diamondback is the largest rattlesnake in the world. Adults are typically four to five feet long and weigh four to five pounds. A big snake may reach six feet in length and weigh 15 pounds or more. The eastern diamondback is distinguished from other snakes by its large size; dorsal pattern of diamonds; yellowish, unpatterned belly; dark tail with rattle; and the infrared-sensitive pit between its eye and nostril.

HABITAT: Eastern diamondback rattlesnakes require large tracts of open-canopy habitats. Although the snakes once thrived in the abundant longleaf pine savannas that characterized the southeastern United States, these habitats have been degraded and destroyed. Shelters from fire and cold are important microhabitats for the eastern diamondback rattlesnake, which sometimes shelters in the burrows of the imperiled gopher tortoise (Gopherus polyphemus).

RANGE: The species can currently be found in North Carolina, South Carolina, Georgia, Florida, Alabama and Mississippi. It is now likely extirpated in Louisiana.

MIGRATION: This species does not migrate.

BREEDING: Mating occurs in late summer and early fall. Ovulation apparently occurs in the late spring of the following year, with births centered on late August and ranging from late July to early October. A pregnant female may retire to a natal shelter a month or two before she bears live young, which are 12 to 18 inches long. Reported clutch sizes range from four to 32. The mother and her newborn snakelings likely stay at the birthing site for seven to 10 days.

LIFE CYCLE: Females reproduce only at two- to four-year intervals, depending on the geographic location, age of the snake and productivity of the environment. Female eastern diamondback rattlesnakes reach sexual maturity at somewhere between two and six years of age. The natural lifespan of an eastern diamondback rattlesnake is probably 15 to 20 years, but evidence from the field indicates that few individuals today live longer than 10 years, likely due to exploitation for the skin trade, vehicle strikes and other human-driven threats.

FEEDING: The eastern diamondback rattlesnake is an ambush predator that feeds on a wide variety of small mammals and some birds. The bulk of its prey consists of rabbits (Sylvilagus species), cotton rats (Sigmodon hispidus) and gray squirrels (Sciurus carolinensis).

THREATS: The primary threats to this snake are habitat destruction, malicious killing by humans, collection for the commercial skin trade and vehicle strikes.

POPULATION TREND: This species' population is declining.

Photo of eastern diamondback rattlesnake by thaths/Flickr