RE: Coyote questions
I would go through your freezer and gather any old meat that you don't want/need. Then I'd go a good distance away from your house and dump it in the woods. Now you can either setup a trail camera to see just how many of these little buggers you're dealing with, or you can just setup to hunt them right there. Another option is to start trapping them, or if you don't want to spend a whole bunch of money, ask someone who traps to take care of them for you.
As far as coyotes attacking humans, they're pretty scared of people, especially if you have a flashlight or lantern with you at night. I don't think they'd tangle with a horse or a St. Bernard either.