Well, its looking like I might have a bit of a fight on my hands. There are now 2 very large great horned (tiger) owls getting braver by the day. Me thinks the male has found a lady. Been going out the last day or two around dusk and walking towards them, they are very people shy, so trying to use that to get them to back off some more. Luckily, Goliath sends off warning calls when they come close, so that helps as well. I know if they get one bird, it will be 100x's harder to get rid of them. I'm guessing just from when they take off, that the male has a wing span of about 4 to 5 feet, the female I would guess somewhere between 3 and 4 feet.