From Wikipedia - the source of all "facts"
Territoriality appears to place a limit on the number of breeding pairs in a given area. Individuals prevented from establishing a territory live a silent existence as "floaters". Radio-telemetry revealed that such floaters concentrate along boundaries of established territories. At Kluane in Yukon, incursions into neighboring territories were observed only twice—by females when neighboring female had died or emigrated, suggesting that territorial defense may be sex specific. At least four dead great horned owls in Kluane were apparently killed by others of their own species in territorial conflicts.[29] Owls killed by other horned owls are sometimes cannibalized, although the origin of the killing may have been territorial aggression.[65] Northern populations occasionally erupt south during times of food shortage,[66] but there is no annual migration even at the northern limits of the great horned owl's range.[29]


We have had a snow white owl on our property two winters back. Illegal immigrant from a special population somewhere in Canada that I have forgotten.

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BrentD, (Professor - just for Stan)
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