Pelecaniformes

order of waterbirds Pelecaniformes (Pelecaniformes) is an order comprising closely related families of organisms. It contains 4 families with 111 known species. This includes the family groups Ardeidae, Balaenicipitidae, Pelecanidae, and Threskiornithidae. Among its members, 20 species are currently classified as threatened (Critically Endangered, Endangered, or Vulnerable). It belongs to Birds (Aves).