アラビアアジサシ Sterna repressa

Sub-tropical tern; slightly smaller than Common Tern with a lighter and less powerful flight, as well as a longer-billed and shorter-legged profile. In all plumages, note the darker upperparts, including the rump and uppertail. Adults have medium dark gray underparts with a dark underwing trailing edge, similar to the shorter-tailed Whiskered Tern. Note that in different light conditions, Common Tern also shows gray underparts, but Common Tern always has a white tail and rump. Young birds are very similar to Common Tern, but White-cheeked Terns are more strongly marked. Breeds on small islands and coral reefs. Vocalisations similar to Common Tern.