The chupacabra or chupacabras, literally 'goat-sucker'; from Spanish: chupar, 'to suck', and cabras, 'goats') is a legendary creature in the folklore of parts of the Americas, with its first purported sightings reported in Puerto Rico in 1995. The name comes from the animal's reported vampirism—the chupacabra is said to attack and drink the blood of livestock, including goats.
Physical descriptions of the creature vary, some describe it as reptilian and alien-like (in Puerto Rico and Latin America), generally as a heavy creature the size of a small bear with a row of spines reaching from the neck to the base of the tail. Others depict it as more dog-like (particularly in Southwestern United States). Sightings have been reported in Puerto Rico since the 1970s, and this creature has since been reported as far north as Maine, as far south as Chile, and even outside the Americas in countries like Russia and Philippines. All of the reports are anecdotal and have been disregarded as uncorroborated or lacking evidence. Sightings in northern Mexico and the southern United States have been verified as canids afflicted by mange. According to biologists and wildlife management officials, the chupacabra is an urban legend.
In 1975, a series of livestock killings in the small town of Moca were attributed to el vampiro de Moca ('the vampire of Moca'). Initially, it was suspected that the killings were committed by a Satanic cult; later more killings were reported around the island, and many farms reported loss of animal life. Each of the animals was reported to have had its body bled dry through a series of small circular incisions.
The first reported attack eventually attributed to the actual chupacabras occurred in March 1995. Eight sheep were discovered dead in Puerto Rico, each with three puncture wounds in the chest area and reportedly completely drained of blood. A few months later, in August, an eyewitness named Madelyne Tolentino reported seeing the creature in the Puerto Rican town of Canóvanas, where as many as 150 farm animals and pets were reportedly killed.
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A five-year investigation by Benjamin Radford, documented in his 2011 book "Tracking the Chupacabra", concluded that the description given by the original eyewitness in Puerto Rico, Madelyne Tolentino, was based on the creature Sil in the 1995 science-fiction horror film "Species". The alien creature Sil is nearly identical to Tolentino's chupacabra eyewitness account and she had seen the movie before her report: "It was a creature that looked like the chupacabra, with spines on its back and all... The resemblance to the chupacabra was really impressive", Tolentino reported.
In late October 2010, University of Michigan biologist Barry O'Connor concluded that all the chupacabra reports in the United States were simply coyotes infected with the parasite Sarcoptes scabiei, whose symptoms would explain most of the features of the chupacabra: they would be left with little fur, thickened skin, and a rank odor. O'Connor theorized that the attacks on goats occurred "because these animals are greatly weakened, [so] they're going to have a hard time hunting. So they may be forced into attacking livestock because it's easier than running down a rabbit or a deer."