Pallid Harrier (Circus macrourus)
Common Tern (Sterna hirundo)
Slender and elegant harrier, with narrow wings and four "fingers". Adult male easily recognized by very pale grey and white plumage, with diagnostic wedge-shaped, black wing-tips (outermost primary grey). Female and immature birds often difficult to tell from Montagu's Harrier and Hen Harrier. Adult female differs from Montagu's by lack of dark band on upper wing, and by diffuse, sooty inner underwing. Pale bands do not reach wingpit, and under coverts are darker. Differs from female Hen Harrier by noticeably slimmer wings (both hand and arm) and only 4 fingers (but beware moulting Hen Harriers). Immature similar to Montagu's with unstreaked, rufous underparts. Differs in pale tips of inner primaries, and dark half-collar and pale "boa".
Sound:Some calls similar to Montagu's and Hen Harrier, but display call quite diagnostic. A thin, vibrating trill "peerrrrrrrr".
Display 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
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