The Aruba Island Rattlesnake (Crotalus unicolor), known locally as the Cascabel, is one of the world’s rarest species of rattlesnake and occurs only on Aruba. It is a stocky, medium-sized snake with a light brown body covered in distinctive pink, blue and brown diamond-shaped markings. Its venom can be life threatening to humans, but the rattlesnake is not considered dangerous because it is not aggressive and will only bite when provoked. Estimates suggest that there are less than 250 adults left in the wild, which is why the species is classified as Critically Endangered (CR) on the IUCN Red List.
Not only is this snake only found on Aruba, but on the island itself its range is now limited to the southern end of the island – development has drastically reduced this snake’s natural habitat, dry rocky areas with cactus scrub. Non-native animals are threatening the long-term survival of this species: Boa constrictors compete for the same food source, and feral goats are destroying its natural habitat. Poaching has also become a serious problem. Aruba Island Rattlesnakes are caught and illegally exported for the pet trade; their rarity makes them an extremely valuable possession.
The good news, however, is that many conservation efforts are now taking place to protect the Cascabel. The Arikok National Park was designated in the early 1980s to include most of the rattlesnake’s population, providing a safe refuge in which the snake can be protected and monitored. The government has also implemented outreach and education initiatives to change local perception of the snake and highlight its ecological and economic importance – it is now being promoted as a national symbol. Arikok’s partnership with the Toledo zoo has safeguarded the rattlesnake ex-situ and led to a number of research projects collecting critical data on the Cascabel’s abundance, life history and habitat requirement to help guide future conservation efforts.