Living Planet Codexery

Eastern Diamondback Rattlesnake

The largest rattlesnake species, endemic to the Southeastern United States.

The eastern diamondback rattlesnake (Crotalus adamanteus) is a species of pit viper in the family Viperidae. The species is endemic to the Southeastern United States. It is the largest rattlesnake species and one of the heaviest venomous snakes in the Americas. No subspecies are recognized.

Scientific Name
Crotalus scutulatus
Maximum Length
123.6 cm (4.1 ft) for males and 92.2 cm (3.0 ft) for females
Primary Habitat
Deserts and other areas with xeric vegetation from near sea level to about 2,500
Diet Type
Carnivore (mostly small rodents and lizards)
Conservation Status
Least Concern (LC) on the IUCN Red List of Threatened Species (v 3.1, 2001)

Lore & Background

The eastern diamondback rattlesnake is the largest rattlesnake species and is one of the heaviest known species of venomous snake, with one specimen shot in 1946 measuring 2.4 m (7.8 ft) in length and weighing 15.4 kg (34 lb). However, other venomous snakes may rival this species in weight such as the much longer but more slender king cobra and the shorter but even bulkier Gaboon viper. Maximum reported lengths for the eastern diamondback rattlesnake are 2.4 m (8 ft) and 2.5 m (8.25 ft). However, the stated maximum sizes have been called into question due to a lack of voucher specimens. Demonstrating rare reverse sexual size dimorphism, males are typically larger than females. Specimens over 2.1 m (7 ft) are rare, but well documented. Klauber (1998) included a letter he received from E. Ross Allen in 1953, in which Allen explains how for years he offered a reward of $100, and later $200, for an 2.4 m (8 ft) specimen, dead or alive. The reward was never claimed. He did receive a number of 2.1 m (7 ft) range specimens and some 2.4 m (8 ft) skins, but said such skins can be taken from specimens as short as 1.8 m (6 ft). A 2.2 m (7.3 ft) specimen was caught and killed outside a neighborhood in St. Augustine, Florida in September 2009. The average size is much less. Specimens are rarely found over 6 feet in length. Lengths of 1.1 to 1.7 m (3.5 to 5.5 ft), and 0.8 to 1.8 m (2.75 to 6 ft) are given. One study found an average length of 1.7 m (5.6 ft) based on 31 males and 43 females. The average body mass is roughly 2.3 kg (5.1 lb). The average weight of 9 laboratory-kept specimens was 2.55 kg (5.6 lb), with a range of 0.8 to 4.9 kg (1.8 to 10.8 lb). Few specimens can exceed 5.12 kg (11.3 lb), although exceptional specimens can weigh 6.7 kg (15 lb) or more. The color pattern consists of a brownish, brownish-yellow, brownish-gray or olive ground color, overlaid with a series of 24–35 dark brown to black diamonds with slightly lighter centers. Each of these diamond-shaped blotches is outlined with a row of cream or yellowish scales. Posteriorly, the diamond shapes become more like crossbands and are followed by 5–10 bands around the tail. The belly is a yellowish or cream-colored, with diffused, dark mottling along the sides. The head has a dark postocular stripe that extends from behind the eye backwards and downwards to the lip; the back of the stripe touches the a

In Their Own Story

Crotalus scutulatus is most active from April to September. They are ambush predators, eating mostly small rodents and lizards. Courtship begins in late summer/fall, is interrupted by winter, and resumes in the spring. Females bear live young, from two to 17 (average about eight), from July through September. This species is not known to den communally and they have no need to seasonally migrate between winter dens and summer foraging areas, as do some other species living at higher elevations and higher latitudes. Instead, individuals occupy well defined home ranges year around, taking shelter during the winter and hot summer weather in burrows excavated by animals like rodents, tortoises, and kit foxes. Like other rattlesnakes, this species is routinely preyed upon by larger predators like coyotes, bobcats, and raptors. As a result, it is shy, cryptic, and does not seek out confrontations with larger creatures, including humans. But like other rattlesnake species, it will strike and bite vigorously when disturbed, especially if surprised or when there is no nearby vegetation or burrow into which the snake can escape.

Reader's Guide

The eastern diamondback rattlesnake is found in the Southeastern United States from southeastern North Carolina, south along the coastal plain through peninsular Florida to the Florida Keys, and west along the Gulf Coast through southern Alabama and Mississippi to southeastern Louisiana. The original description for the species does not include a type locality, although Schmidt (1953) proposed it be restricted to 'Charleston, South Carolina' (USA). This snake species is classified as Least Concern on the IUCN Red List (v3.1, 2001). Species are listed as such owing to their wide distribution or presumed large population, or because they are unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend was down when assessed in 2007. In North Carolina, the eastern diamondback rattlesnake is protected by state law and considered endangered within the state. It is likely extirpated in Louisiana, having last been observed there in 1995. In fact some scientists and conservationists believe it may even be extirpated in North Carolina, having last been observed there in the early 1990s. This species is currently under review for being added to the Endangered Species List by the United States Fish and Wildlife Service owing to its recent decline, and the current population represents only 3% of the historical population. Eastern diamondback rattlesnakes (Crotalus adamanteus, EDB) have limited ability to adapt to habitat loss and fragmentation due to the species' slow life history, high habitat specificity, and minimal dispersal ability. Threats to eastern diamondback rattlesnake include habitat loss, killing by humans, and highway mortality. Rattlesnake roundups are another threat to this species, as they are removed from the wild and killed for exhibition and entertainment. One common method of capture at these events involves pouring gasoline down a rattlesnake's supposed burrow, a practice which is harmful to both the snake and its environment. A study was conducted in South Carolina that showed positive results in translocating species to save them due to their inability to adapt to habitat loss. The eastern diamondback rattlesnake inhabits upland dry pine forest, pine and palmetto flatwoods, sandhills and coastal maritime hammocks, longleaf pine/turkey oak habitats, grass-sedge marshes and swamp forest, cypress s

Did You Know?

More in Reptiles & Amphibians

Elsewhere in the Living Planet universe

Spotted an error? Know more?

This is a living reference — every entry is fact-audited, and reader corrections feed straight into our audit queue. Suggest an edit · See this site's audit record

Comments

Loading…
Open in the interactive codex →