I caught sight of a couple of Black-Bellied Whistling-Ducks with Ducklings in a freshwater pond in Vero Beach, Florida. These tree ducks are called Black-Bellied Whistling ducks and they have bright orange bills and legs. Their nesting habit involves trees, cavities, nest boxes, and occasional ground scrapes. They’re one of two types of Whistling Ducks in North America and they make a whistling sound while flying. The young ducklings are tended by both parents until they can fly and fend for themselves, usually around 2 months old.