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Name: Lori
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We live in Central Illinois. We have lots of hummingbirds in our yard. About two weeks ago, they started diving at each other while they are feeding. The first part of the summer, they left each other alone, now it seems they are trying to attack each other. Can you tell me why they are displaying this behavior now?

August is post breeding dispersal time for hummingbirds in Illinois, a lot of the birds coming to feeders now are young of the year, along with dispersing adults. Young birds may be "testing" their territorial instincts, and hummingbirds tend to be rather pugnacious anyway. Earlier in the year, during the breeding season, territories are more firmly established and dominance more or less worked out, so there is less visible aggression, though it occurs at all times. Enjoy!

J. Elliott

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