How Fast Can Birds Fly?

Peregrine Falcon

Most cruise speeds of birds are in the 20-to-30-mph range, with an eider duck having the fastest accurately clocked air speed of about 47 mph. During a chase, however, speeds increase; ducks, for example, can fly 60 mph or even faster, and it has been reported that a Peregrine Falcon can stoop at speeds of 200 mph (100 mph may be nearer the norm). Interestingly, there is little relationship between the size of a bird and how fast it flies. Both hummingbirds and geese can reach roughly the same maximum speeds.

http://en.wikipedia.org/wiki/Peregrine_Falcon