After reading from multiple sources, one should easily come up with several possibilities for the goat sucker known as the Chupacabra:
1) It is just a hoax, with people's imagination running wild while trying to figure out what in the hell could have sucked the blood out of their goat or whatever. By the way, whatever it is, goats are not the only victims... Cows, chickens, etc., have all been victimized by this blood sucking technique that is often accredited to the Chupacabra.
2) Yeah, the aliens dropped it off from the spaceship, just to give us something else to think about and to cause a little havoc on random farms and whatnot.
3) These outlandish little devils are just dogs with the mange and/or coyotes and raccoons with parasitic infections and other health-related problems that causes their otherworldly appearance.
4) Someone must have did some experiments, aliens or humans, and altered the DNA and created some mutated beast that, for whatever reason, must have got loose or set free for a reason and has multiplied and mastered the art of strategic travel, since the time of their initial release. Also, their strange genetics gave them the ability to out-suck the mythical vampires, as well.
5) Who knows; who cares, just so that bastard doesn't show up at my doorstep.
Additional reading and resources about the Chupacabra:
"Like other creatures in the cryptozoologist's barnyard, the chupacabra has been variously described. Some witnesses have seen a small half-alien, half-dinosaur tailless vampire with quills running down its back; others have seen a panther like creature with a long snake-like tongue; still others have seen a hopping animal that leaves a trail of sulfuric stench. Some think it may be a type of dinosaur heretofore unknown. Some are convinced that the wounds on animals whose deaths have been attributed to the chupacabra indicate an alien presence. However, they do not attribute the "mutilations" to the aliens themselves, but to one of their pets or experiments gone awry. Such creatures are known as Anomalous Biological Entities [ABEs] in UFO circles." Read more... http://skepdic.com/chupa.html
"The chupacabras (from chupar "to suck" and cabra "goat", literally "goat sucker") is a legendary cryptid rumored to inhabit parts of the Americas. It is associated more recently with sightings of an allegedly unknown animal in Puerto Rico (where these sightings were first reported), Mexico, and the United States, especially in the latter's Latin American communities. The name comes from the animal's reported habit of attacking and drinking the blood of livestock, especially goats." This wikipedia link has quite a bit of info on the Chupacabra subject. I found the "Reported Sightings" section to be somewhat interesting. Read More... http://en.wikipedia.org/wiki/Chupacabra
Look out folks...---End of Post "Chupacabra - Goat Sucker?"