The shoebill stork (Balaeniceps rex) is a large wading bird with a giant beak that makes a loud, machine-gun-like sound when it claps its bill together. This behavior, called "bill-clattering", is used to attract mates and greet other shoebills, especially when they're near their nests. The sound can also be described as quick, repetitive bursts that resemble tribal drums | Christian Studies | Facebook