The terns are seabirds in the family Sternidae, previously considered a subfamily Sterninae of the gull family Laridae. They are less closely related to the waders, auks and skimmers.
Most terns belong to the large genus Sterna. They have a worldwide distribution.
Many terns breeding in temperate zones are long-distance migrants, and the Arctic Tern probably sees more daylight than any other creature, since it migrates from its northern breeding grounds to Antarctic waters.
They are in general medium to large birds, typically with grey or white plumage, often with black markings on the head. They have longish bills and webbed feet. They are lighter bodied and more streamlined than gulls, and look elegant in flight with long tails and long narrow wings.
Most typical Sterna terns hunt fish by diving, often hovering first, but the marsh terns pick insects of the surface of fresh water. Terns do not glide or swim.
- Suborder Charadrii: The waders.
- Suborder Lari
- Family Laridae (gulls)
- Family: Sternidae
- Gull-billed Tern, Sterna nilotica
- Little Tern Sterna albifrons
- Least Tern Sterna antillarum (Often considered conspecific with Little Tern).
- Lesser Crested Tern Sterna bengalensis
- Arctic Tern Sterna paradisaea
- Common Tern Sterna hirundo
- White-cheeked Tern Sterna repressa
- Caspian Tern, Sterna caspia
- Elegant Tern, Sterna elegans
- Sandwich Tern, Sterna sandvicensis
- Chinese Crested Tern, Sterna bernsteini
- Royal Tern, Sterna maximus
- Great Crested Tern, Sterna bergii
- River Tern Sterna aurantia
- Roseate Tern, Sterna dougallii
- White-fronted Tern, Sterna striata
- Black-naped Tern, Sterna sumatrana
- South American Tern, Sterna hirundinacea
- Antarctic Tern, Sterna vittata
- Kerguelen Tern, Sterna virgata
- Forster's Tern, Sterna forsteri
- Trudeau's Tern, Sterna trudeaui
- Saunders' Tern, Sterna saundersi
- Yellow-billed Tern, Sterna superciliaris
- Peruvian Tern, Sterna lorata
- Fairy Tern, Sterna nereis
- Damara Tern, Sterna balaenarum
- Black-bellied Tern, Sterna acuticauda
- Aleutian Tern, Sterna aleutica
- Grey-backed Tern, Sterna lunata
- Bridled Tern, Sterna anaethetus
- Sooty Tern, Sterna fuscata
- Black-fronted Tern, Sterna albostriata
- Black Tern Childonias niger
- White-winged Black Tern or White-winged Tern Childonias leucopterus
- Whiskered Tern Childonias hybridus
- Large-billed Tern Phaetusa simplex
- Brown Noddy Anous stolidus
- Black Noddy Anous minutus
- Lesser Noddy, Anous tenuirostris
- Blue Noddy, Procelsterna cerulea
- Grey Noddy, Procelsterna albivitta
- White Tern, Gygis alba
- Inca Tern Larosterna inca
- Family Stercorariidae (skuas)
- Family Rhynchopidae (skimmers)
- Suborder Alcae The auks.