People walking along the river walk trail east of Battell Park say some of the birds, including a red-winged blackbird, have been aggressive towards them.

According to bird experts, the birds may be protecting their nests or acting dominant to attract a female.

The aggression has some neighbors feeling uneasy.

"They say that if you come across one, just keep your eye on it because they wait for you to turn your back," said Colin Ullery, who was attacked by one of the birds.

The birds may not be leaving any time soon.

Blackbirds typically mate until July and chicks could be in the nest until August.