The monster out back

How was your 4th of July? Mine was eventful. My parents were up for part 342 of the kitchen remodel saga. It is soooo close to done. A few more handles on cabinets and a light fixture are all that stand between you and more pictures. 

Since I'm sticking to my promise to hold off on showing the finished kitchen until it's, you know, finished, I instead ask for your assistance in solving this mystery:

These are my dogs:

I know, ferocious. These dogs usually take several tours per day of the backyard to do their business and run security rounds to determine whether anything fun to play with has made an appearance since their last outing. As of this past Saturday, Luna is completely uninterested in going out there after dark. Cora isn't too thrilled with the idea either, but she'll go if I go. Saturday night they both came in panting to beat the band and Luna had some cuts on her face. Before you worry too much, let me just say that cuts on Luna are not generally a cause for major concern. Her attitude is most often similar to a battering ram when it comes to getting into things. This time, though, something had obviously scared them but good. I didn't hear any fireworks going off while they were out there. Therefore, I am going with the most obvious conclusion:

There must be a chupacabra in my backyard. Does anyone have advice on how to escort this to another area?