Sandwich Tern (Thalasseus sandvicensis)
Black-headed Gull (Chroicocephalus ridibundus)
Large tern with black bill, with yellow tip (adults). Bill all black in juveniles. Long black cap and shaggy crest. Generally leaves a much whiter impression than other terns in the region (except Roseate Tern). Adult summer: Yellow bill-tip. Tail pure white, and upperparts pale grey. Outer primaries darker than rest of wing, and contrast increases in worn plumage. Broad white trailing edge to inner wing. Underside of primaries with faint narrow dark trailing edge. Forehead white in adult winter and first winter plumage. Juveniles: scaly upperparts and dark bill. Less evenly coloured than juvenile Gull-billed Tern. First winter birds similar to juveniles, but back purer grey and bill shorter. Can be mistaken for Gull-billed Tern, but note different profile. Flight powerful with evenly narrow wings and a front-heavy appearance, due to the long head and bill. Often dives from high above the surface and stays under water longer than Common and Arctic T.
Sound:Contact call a sharp and grating "keeree-eek". Often compared to the pressing of amalgam into a tooth.
Contact call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCChocolate-brown hood in adult plumage (seemingly black at a distance), but head only with dark markings in winter and juvenile plumages. Underparts of inner primaries dark grey. First few primaries white with black tip, both on upper side of wing and under. Last character conspicuous in all plumages, but slightly less obvious in juveniles due to larger dark area of wing-tip. Slender-billed Gull and Bonaparte's Gull show similar white first primaries, but differs in long and slender head profile and white underparts of hand respectively.
Sound:Quite vocal, especially at breeding ground. Distinct, harsh calls. A rasping "kreearr", and shorter, sharp warning calls; "kek".
Contact call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC