Pellets are the solid waste of owls; the gizzard compacts all the bones and fur, which the owl cannot digest, and regurgitates, or "yarps" it up through its beak. Owls and nest-maid snakes call birds who cannot yarp "wet poopers," a highly offensive term. However, softer, more digestible food material is converted to, and passed as, liquid droppings.
- Owls aren't the only birds that regurgitate pellets. Other bird species that do so include grebes, cormorants, herons, vultures, hawks, falcons, kestrels, shorebirds, gulls, terns, kingfishers, kingbirds, crows, ravens, jays, dippers and shrikes.