There is nothing that is going to protect birds against wolves. (Except for a rifle.) Anything that you could get to supposedly "guard" them would just me even more "wolf bait". A Llama, alpaca or even a donkey would all easily be killed by a wolf. (And IMO, Llamas being great guard animals is not really that true. If it were, why would a lot of Llama breeders have livestock guard dogs to protect their llamas? And this is in places where they largest predators are coyotes and dogs.) IMO, you either need to get used to loosing animals, OR pen them up somehow. A donkey might work against a lynx. IF it is the "right" donkey. Because they aren't all created equal as far as protecting their "herd mates". Heck, the donkey might take out the birds itself.