Arctic Warbler (Phylloscopus borealis)
Common Tern (Sterna hirundo)
Like a large Willow Warbler, with distinct dark eye-stripe. Supercilium marked, but narrow. Starts at base of bill, continuing far behind eye. Wing-bar distinct on greater coverts, and sometimes on median coverts too. Primary projection long. Bill long and relatively heavy with orange base. Flanks often slightly grey, and throat sometimes with faint streaking. Appearance robust, but elegant. Moves faster and with more confidence than congeners.
Sound:Call and song diagnostic. Song a rattling series of 20-30 single syllables. Repeated as a monotonous phrase in stable pitch, lasting 2-4 seconds. Starts more softly with volume rising throughout each phrase. Contact call equally unique. A hard and short "tsrrt", recalling contact call of Dipper. Often given as introductory part of song.
Song (two variants) and calls:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCDiffers from Arctic Tern in longer head, and more orangy red, rather than deep red, bill. Tip of bill usually black. Legs longer, but tail streamers shorter than AT. Underparts of primaries with diffusely bordered dark trailing edge (sharply bordered in Arctic Tern). Upper side of primaries with dark wedge (less apparent in winter). Secondaries opaque. Crest more apparent than in Arctic Tern and underside whiter. Juveniles with buff back.
Sound:Similar to Arctic Tern but deeper. Lacks latter's high pitched "tip-tip-tip" call, and the drawn out "kree-aaahh" call falls more distinctly in pitch.
Call:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC