Barred Owls are very territorial, and they don’t migrate. Solitary calls from a male in early spring probably mean that he has not attracted a mate.
In May and June, he continues to hoot, though less frequently.
By summer, breeding season has passed. Maybe this solitary Barred Owl is what some scientists call a "non-breeding floater". Perhaps his patch of woods is just too small to host a pair of owls year round.
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