This animal, also known as "the goat sucker", is well known in Mexico and Puerto Rico. It got its name when some goats turned up dead with puncture wounds in their necks and totally drained of their blood. But what is it exactly?
There's no one answer to that question. From the thousands of eyewitnesses, several so called "descriptions" of the creature have been noted. Some say its half alien, half dinosaur. Others describe it has a panther with a snake-like tongue. It's even been linked to aliens. Of course, when aliens involved, theories of a mass government conspiracy aren't far behind.
The attacks began around 1995 and have claimed around 2,000 animal deaths. Authorities in Puerto Rico claim that it doesn't even exist. They explain the attackers to just be stray dogs or other animals. They go on to say that the "Chupacabra cases" show nothing unusual to suggest such an animal exists.
Is it possible that this creature does exist? Sure, anything is possible. The chupacabra could just be another link in the chain we call the Circle of Life. Until more compelling evidence comes forth, el chupacabra will remain another mystery of life.
More info: http://skepdic.com/chupa.html
*Carroll, Robert Todd (2005). Chupacabra. Retrieved on July 26, 2005 from the Skeptic's Dictionary website: http://skepdic.com.