The dominant bird in my area is a Brewers Blackbird, about the size of a starling, they aggressively run off any crows. So I have probably 70 to 80 nests of Brewer's Blackbirds and a couple hundred of other birds that use them for defenses. It's been 3 years since the crows went after the nest of one of the pairs of doves and 45 birds ran off the first crow when the second one came in there was only 15 available and they got it right out of there too.
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