a PBS special on crows/ravens points out that they are the only birds known to fly closer to the sound of a gun shot.

they have learned that human's who are shooting, (and eventually sucessfull) will 'field dress' the game..and leave the liver and other tasty entrails for the crows to feast on.

(not that i am much of crow lover myself. i used to hate them.. but i miss them now. West Nile Virus was very hard on NYC's crow population--other birds didn't seem to suffer as much as the crows did)