The common grackle with an uncommon attitude.
Male Mute swan defending his territory in mating season. This was taken from my kayak, just before I retreated to safety.60D with 100-400mm
I am not sure if this is the type of attitude that you are after, but this Sulphur Crested Cockatoo was certainly giving passers by a lot of attitude by swearing at them.I am not a fan of birds in small cages, and this guy would normally have a much larger aviary to fly around in but he was being quarantined in a small cage after getting a treatment from the vet, and he was not happy about it.Sulfur Crested Cockatoo behind bars by Idiot4Hire, on FlickrShot with an 1100D with an ef-s 55-250mm lens.
Calling the flockTree Swallow - Martha's Vineyard100-400 mm