A British Columbia hunting forum has an account of a wolf attack:
So, yesterday a friend an I took our families out sliding and ended up having a little more excitement than we had anticipated.
There we were having a good time......Rod was towing 3 of the kids (2 four yr olds and a 3 yr old) on a tobogan behind the quad, at the bottom of the hill. I was in the Argo with my 3 month old at the other end of the hill. Rods wife was warming up in the truck with there 2 yr old and my wife was at the top of the hill with our dog...........we had no idea that all hell was about to break loose.........
Two wolves appear out of nowere............and they are heading toward the kids dragging behind the quad.... at first I had no idea what was up, but I heard my wife start yelling. I look up at her and see the dog break out of her arms and start running like mad, diagonally down the hill toward the truck (the direction Rod was heading with the kids). Rod sees the wolves coming, just as he is getting close to the truck, he speeds up a little, but can't go too hard for fear that one of the kids might fall off. As he gets to the truck the wolves are about 20 feet from the kids, on the tobogan. Rod bolts back toward the kids, just as my dog "Shadow" intercepts the lead wolf. Teeth flash and the battle is started............
Fortunately, no humans were seriously hurt, and the dog is okay, too. Fortunately, the humans involved had guns.
Read the forum for the full story, including pictures.
Wild animals are dangerous, and represent a threat to humans at the fringes of civilization. But some humans are afraid to restrict these predators.
Some animal rights activists ask, what is it that really separates us from animals? Other than the Terminator reason (humans are self-aware), there's also this: Humans are the only species that will hurt themselves for the benefit of another species.
Found via the Actuarial Outpost, where the discussion is also interesting.