Royal tern Sterna maxima

Identification Tips:

Adult alternate:

Adult basic:



Similar species:

When identifying terns, it is safest to use a combination of field marks instead of relying on a single characteristic. Elegant Terns are slightly smaller and slenderer, with more slender, drooping bills and, when not in alternate plumage, lack a pale eyering in the dark mask. The Caspian can be separated from the Royal by its thicker, reddish bill, dark wedge on the outer portion of the underwing, its more shallowly-forked tail and its tendency to have an almost complete cap in basic and immature plumages. The smaller Sterna terns have slimmer, black or black-tipped bills, slimmer bodies and wings and a much more deeply-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.