Tropical birds known for their massive bills, hornbills include 32 Asian and 27 African species in the avian family Bucerotidae. Many hornbills have a casque on their upper mandible, which in some species is spectacularly colorful. Many species also share a unique breeding strategy, in which nesting females incubate eggs and raise chicks inside sealed natural tree cavities for up to 100 days, depending entirely on males to bring them food.
