Eastern pygmy rattlesnake, Ground rattlesnake, Leaf rattler, Death rattler
The Pygmy rattlesnake (Sistrurus miliarius) is a small venomous snake native to the United States. It is a member of the pit viper family. Pit vipers have a heat-sensing pit organ located between the eye and the nostril on both sides of the head; these organs are of great value to a predator that hunts at night, as well as for avoiding the snake’s own predators.
The dorsal pattern of these snakes consists of a series of oval or subcircular spots with somewhat regular edges. The spots on the flanks are mostly round and not much higher than they are wide. Belly pigmentation towards the rear is more limited to indistinct blotches found on pairs of adjacent scales. Juveniles' color patterns are similar to the adults, although they may be paler or more vividly marked, and the tips of their tails are yellow.
Pygmy rattlesnakes are found in the Southeastern United States from southern and eastern North Carolina, south through peninsular Florida, and west to East Texas and Oklahoma. These snakes tend to live in flatwoods, sandhills, mixed forests, and floodplains. They are also found near lakes and marshes.
Pygmy rattlesnakes are generally solitary and interact with each other only during the mating season. They are diurnal and usually seen in the summer sunning themselves or crossing the road late in the day. Pygmy rattlesnakes do not dig their own burrows but rather use those dug by small rodents or Gopher tortoises. These snakes hunt their prey by active pursuit, grabbing and flipping it around while simultaneously injecting venom to prevent injury by the victim. They also ambush lizards such as skinks by using their tails as lures, as is common in many other species of vipers. These snakes have a tiny rattle which makes a buzzing sound that can only be heard from a few feet away. Some individuals are very aggressive and strike furiously, while others seem lethargic and do not even attempt to rattle.
Pygmy rattlesnakes are unable to produce much venom and are unlikely to be able to deliver a fatal bite to a human adult. They produce cytotoxic venom that is strongly hemorrhagic and tissue toxic, but devoid of any neurotoxins. The venom was the basis for the development of the drug eptifibatide, which is used to prevent clotting during a heart attack. The venom is somewhat different in that it contains substantial amounts of serotonin and related tryptamine compounds.
Pygmy rattlesnakes are carnivores (insectivores). Their diet includes small mammals and birds, lizards, frogs, and insects including giant desert centipedes. They also feed on other snakes.
Pygmy rattlesnakes are monogamous and only one male mates with a female. He will continue to stay close to the fertilized female during her pregnancy and they can sometimes be seen coiled around one another. Pygmy rattlesnakes breed in spring and give birth to live young. The gestation period lasts from 3 to 5 months and litters usually consist of 2-12 young. Snakelets are born precocial (fully developed) but stay near their mother first 7-10 days of their life for protection. They become reproductively mature at 2 years of age.
There are no major threats to Pygmy rattlesnakes at present.
According to IUCN, the Pygmy rattlesnake is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Pygmy rattlesnakes are important for their ecosystem as both a predator and a prey species. They prey on insects, small mammals, amphibians, and other small snakes thus controlling their populations. In turn, these snakes are preyed upon by hawks, owls, raccoons, kingsnakes, and other local predators.
