Black Vultures eat carrion mostly. It may scavenge at garbage dumps, but also takes eggs and decomposing plant material and can KILL or INJURE new-born or incapacitated mammals. also occasionally feeds on livestock or deer. It is the only species of New World vulture which preys on cattle. It occasionally harasses cows which are giving birth, but primarily preys on new-born calves. In its first few weeks, a calf will allow vultures to approach it. The vultures swarm the calf in a group, then peck at the calf's eyes, or at the nose or the tongue. The calf then goes into shock and is killed by the vultures. Toshabell, as for the talon marks on the hen you found, it 'probably wasn't a vulture , their feet are flat, fairly weak, and are poorly adapted to grasping; the talons are also not designed for grasping, as they are pretty much blunt. Other birds of prey can look similar from a distance. We have several puulets from this year that escape their protective enclosure and wander around near our ruined barn, where a Black Vulture has been brooding the last four years. She has two young right now, and has not 'yet' killed any of our birds. The roosters put up an alarm call that lasts about four minutes whenever she rousts herself in the morning, so they definitely are threatened by her. Turkey Vultures (Buzzards) are characteristicly similar to Black Vultures. Basically, keep an eye on your birds when they are out in the yard.
=Fitz