List of Gaviiformes by population

This is a list of Gaviiformes species by global population. While numbers are estimates, they have been made by the experts in their fields. For more information on how these estimates were ascertained, see Wikipedia's articles on population biology and population ecology.
This list follows IUCN classifications for species names. Where IUCN classifications differ from other ornithological authorities, alternative names are noted. The IOC World Bird List recognizes 5 species of Gaviiformes. IUCN/BirdLife International have assessed the populations of all members of this order.