Gull-billed tern
Sterna nilotica
Identification Tips:
- Length: 13 inches Wingspan: 35 inches
- Sexes similar
- Medium-sized, robust tern
- Thick, blunt, black bill
- Short, notched tail
- Pale underwings
Adult alternate:
- Black legs
- Black cap
- White face, neck, breast, and belly
- Pale gray back and upperwings
Adult basic:
- Similar to adult alternate, but has a white forehead and dark streaking
about the rear of the head, and variable dark ear spot
Juvenile:
- Similar to adult basic but mantle has brownish spots
Similar species:
The Gull-billed Tern can be identified in all plumages by its thick,
relatively short, black bill and shallowly forked tail.
Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds of North America. New York: Western Publishing Company, Inc.