Birds are less sensitive to the high and low ends of their range than mammals, but in the middle frequencies it is similar. However, birds are about 10x as sensitive to rapid fluctuations in pitch and intensity than humans. A few birds use echolocation, like bats. The Oilbird and the Cave Swiftlet of southeast Asia are examples. They use echolocation to navigate but not to catch prey.
Recent evidence indicates, however, that penguins can locate prey via echolocation.
Both Darwin and Audubon showed that vultures did not find carcasses if they were covered. Audubon painted a picture of a dead sheep and vultures tried to eat it. There is also an anecdote about Black Vultures attacking and eating a spraying skunk. Albatrosses, skuas, and petrels in the Antarctic seem to be able to detect meat, fat, or blood spread on the sea's surface. Evidence indicates that African Honeyguides can locate beehives by the odor of the wax.