Danes have historically been used as guard dogs, and still have
the guardian temperament in them, even though that has been
eventually bred out of them. As far as guarding its human against a
threatening bear is concerned, the Great Dane will do its best to
keep that bear away from the human. He may not win in a potential
fight, but at least he'll do his darnedest to keep the bear
occupied long enough for his human master to get away to
safety.