That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information
Occasionally I like to highlight animals that, while not suitable as pets, are none-the-less of great interest to reptile enthusiasts. The Aruba Island Rattlesnake, Crotalus unicolor, native to a place known more for its resorts than for reptiles, is one such beast…from diet to range to appearance, it is most unique.
Please Note: I’ve had the good fortune of working with Aruba Island Rattlesnakes at the Bronx and Staten Island Zoos. This came about in connection with a lifetime of training and experience, supported by an emergency response team that would assure rapid care in the event of a bite. I would not keep venomous snakes in my private collection, nor should anyone.
Description
Despite the “plain-sounding” species name (unicolor), the Aruba Island Rattlesnake is a beautiful animal. Individuals vary greatly, and may be pale-gray, pinkish-gray or gray-brown in color, with pale-brown rhomboid markings down the back. Their subtle hues match the rocky habitats they frequent. The stoutly-built adults typically average 24-30 inches in length, but occasionally reach 3 feet.
The Aruba Island Rattlesnake was once considered to be a subspecies of the Neo-tropical Rattlesnake, Crotalus durissus.
Range
This species is limited to the southern tip of Aruba Island (Netherlands Antilles), 15 miles off the coast of Venezuela. Its entire range covers a mere 10 square miles.
Habitat
The Aruba Island Rattlesnake is found only in those few areas of the island that are largely inhospitable to people. It frequents rocky hillsides, arroyos and adjacent rock-sand fields, among cactus and thorn-scrub.
Status
Found only within 10 square miles of an already tiny natural range, this snake is threatened by resort development, habitat destruction (largely due to the activities of feral goats), and, at least in the recent past, collection for the pet trade.
It is protected by the government of Aruba, designated as “Threatened” by the US Fish and Wildlife Service, “Critically Endangered” by the IUCN and listed on Appendix II of CITES.
The Aruba Island Rattlesnake breeds well in captivity and is currently the subject of a zoo-based Species Survival Plan, field studies and an education program onAruba. It has recently been featured on the island’s postage stamps and currency. Eradication of feral goats, to preserve remaining habitat fragments, is being considered.
Conservation efforts are hampered by the fact that the snake is venomous and its range has long been heavily utilized by people.
Longevity
Captive longevity approaches 20 years; unknown in the wild.
Reproduction
Mating occurs from September through January. The young, 2-9 in number, are born alive after a gestation period of approximately 240 days. They average 8-11 inches in length and feed primarily upon lizards and frogs.
Diet
Rats, mice, lizards, frogs, birds and, possibly, bats.
It is interesting to note thatArubahas no native terrestrial mammals other than bats. In contrast to other large rattlesnakes, this species must have subsisted largely upon reptiles, birds and amphibians prior to the introduction, by people, of Norway Rats and House Mice.
Other Rattlesnakes
The following information is taken from an article I wrote on the Natural History of Rattlesnakes. Please see the original article to learn more about these fascinating creatures.
Rattlesnakes and their relatives, collectively known as “pit vipers”, are classified in the subfamily Crotalinae, along with palm vipers, copperheads, cottonmouths and related species. They are considered to be the most advanced, or highly evolved, of the snakes. All possess a sophisticated organ that detects the infra-red rays (heat) produced by birds and mammals.
Rattlesnakes are confined to the Western Hemisphere, and reach their greatest diversity in the American Southwest and Mexico. Thirteen of the 33 known species are found in Arizona alone. Only 4 species range east of the Mississippi (Eastern Diamondback, Eastern Massasauga, Pigmy Rattlesnake, Timber Rattlesnake) while South America is home to but 2 species (Neo-tropical Rattlesnake, Uracoan Rattlesnake).
The rattle, unique among snakes, is composed of a series of loosely-connected segments. Specialized muscles in the tail vibrate the rattle to produce the characteristic warning sound.
All rattlesnakes bear live young and some species appear to provide a degree of parental care to their offspring. The Black-tailed Rattlesnake has been shown to recognize siblings after a 2 year separation.
Rattlesnakes and other vipers have evolved long, hinged fangs that fold back against the roof of the mouth when not in use. Venom is injected with a single bite, in the manner of a hypodermic needle.
Further Reading
American Zoo Association Studbook (inventory of captives) and conservation strategy
Video: ArubaIs Rattlesnakes courting
Aruba Island Rattlesnake videos, photos and facts
Aruba Island Rattlesnake image referenced from wikipedia and originally posted by Ben Lunsford
Neoptropical Rattlesnake image referenced from wikipedia and originally posted by LtShears
