Today on the Vis Mig email group there was some talk about Comic Tern ID. So I thought I’d post something on the subject, something which I have spent years learning through watching inland reservoirs and visiting various breeding sites.
Adult summer Common Tern - firstly the dark outer primaries strongly contrasting against the pale grey inner primaries. Supporting this the short tail streamers, orangey red bill which in long and dark tipped
Adult summer Arctic Tern - the best feature is the uniform upper wing (no black wedge), also the long trail streamers, dusky underparts, short blood red bill and hair line trailing edge to the underwing
Adult summer Common Tern - showing the thick smudged dark trailing edge to the underwing (this is restricted to the outer primaries). Also visible here is the barrel shaped body
Adult summer Arctic Tern - this picture illustrates two important features, the hair line trailing edge on the underwing and the heavy chested look. Comparing to the Common Tern above, the slimmer wings are very obvious creating a distinctive look.
Adult summer Common Tern - some look more uniform across the upperwing but the dark wedge is still present just not so obvious. Note the thicker wings, short tail streamers and typical long orange/red bill with a dark tip
Adult summer Arctic Tern - here you can see the elegant structure of this species. The long thin wings and the long streamers stand out well
Adult summer Common Tern - an attempt to show the translucent underwing which is restricted to the inner half of the primaries
Adult summer Arctic Tern - you can just about see the completely translucent underwing which runs from the base of wings out to the tips
Adult summer Arctic Tern - here you can see the elegant structure of this species. The long thin wings and the long streamers stand out well
Comentários