"Almost immediately, everywhere the show aired, suddenly people were seeing the chupacabra," he said. "If you go back and look at it, the media actually played a very strong role in promoting the chupacabra."
But Radford said that when he spoke with Tolentino during his research for the book, he found her detailed description of the chupacabra was too detailed. In fact, he said, it was "suspiciously detailed."
And, during their interview, Radford said, Tolentino revealed that just weeks before her mysterious sighting, she had seen the hit science-fiction movie "Species," which features characters that look much like the chupacabra of her memory.
"To me, that was the smoking gun," he said. "It can't be a coincidence that this chupacabra that's now popping up around the world just happens to look exactly like the monster in this sci-fi film."
But Radford said he doesn't think Tolentino is a liar or hoaxer, just that she confused something she saw in a movie with something she saw in real life.
And he said that considering the context, it's even more understandable.
"This didn't occur in a vacuum," he said. "At the time in Puerto Rico, there was already a pre-existing belief that something weird was going on. ...People were finding dead animals."
Now, he said, it's clear that those dead animals didn't die mysteriously but after attacks by dogs, mongooses or other animals. At the time, however, "Her description put a face and form to a previously amorphous and vague sense of something being weird."
Radford said that a separate category of chupacabras started appearing in southwestern parts of the U.S. and other Spanish-speaking regions of the world in the mid-2000s, but could be explained away by DNA evidence (although that hasn't stopped reports from popping up every so often).
In those reports, the so-called chupacabras are reported as hairless, coyote-like creatures that stand on four legs. But Radford said that forensic science and DNA evidence has shown those to be mangy canids – dogs, foxes and coyotes with a skin disease called sarcoptic mange.
It's a contagious skin disease, caused by mites, that affects many dogs and results in hair-loss, he said. They tend to be spotted more in warmer climates because they die off in colder weather.
Next time you hear a report of a chupacabra sighting, Radford says you should examine the evidence and not blindly believe what you read. But he also says that despite his book -- and the case he says he's solved -- people will continue to tell the tale of the mysterious chupacabra.
"It doesn't matter what I write, it doesn't matter that I solved this. People are still going to see a weird hairless thing and someone is going to call it a chupacabra," he said. "I think the bigger answer is that people like mysteries. And the idea of a Hispanic beast that sucks goats' blood is kind of cool -- it captures the public's imagination."