The Audubon Bird Call works. It makes a variety of tweeting, squeaking and chirping noises that provoke the curiosity of various bird species, attracting them to the location of the user.
The Audubon Bird Call, which is made by American Bird Products, has been popular since its invention by Roger Eddy in 1947. Ornithologists are not certain why the device works, but the dominant theory is that the sounds it makes are similar to the alarm calls of birds. When birds give alarm calls, other birds come to their rescue and give similar alarm calls to attract more birds. The birds then collectively harass and attack the predator, a behavior known as mobbing.