Aruba island rattlesnake in exhibit

Aruba Island Rattlesnake

Scientific Name
Crotalus unicolor
Geographic Range
Aruba (in the Caribbean off the coast of Venezuela)
Rodents, lizards, and birds
Aruba Island rattlesnake in exhibit Endangered Status Graph - Not Evaluated Endangered Status Graph - Not Evaluated

More Information

Aruba Island rattlesnakes are less than 1 meter long, with pale tan scales and diamond-shaped patterns on their backs. Like other pit vipers, they are heavy-bodied with triangular heads and rattles at the tips of their tails. They can unhinge their jaw to eat prey whole. These solitary reptiles prefer arid, thorn scrub, and desert habitats. Because of Aruba’s warm environment, they are active year-round and can be more active at night.

Males fight for females’ attention, but do not use venom for these battles. Their young hatch from eggs that are fertilized and incubated for about four months inside the bodies of the females (ovoviviparous). Five to 15 young are produced per clutch, and they are fully independent at birth. They become mature at 4–5 years.

Did You Know?

  • While the species has not been evaluated by the International Union for Conservation of Nature, Aruba Island rattlesnakes are considered one of the rarest rattlesnakes in the world. They are also the top terrestrial predators on the island.
  • These snakes have one heat-sensing pit on each side of their nostrils to detect prey. They also hunt by sight and smell.
  • To attack prey, they position themselves with an S-shaped neck and then strike with their fangs to deliver venom.


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