When birding at
Sabkhat Al Fasl 20 November 2015 with visiting birder Edward Pollard we found a
very dark White-winged Tern. I see many White-winged Terns during the year at
this site, including a number on the same day as this one, but this one was
particularly dark. The dark colouration made the bird look like a Black Tern
and its active flight made it difficult to get any real features on. I managed
to grab a few photos as the bird flew quickly past and it can be seen from
these that the bird lacked many of the features of Black Tern such as the
normally obvious breast patch. Other features pointing towards White-winged
Tern included square-tipped tail with paler outer tail feathers, head pattern
and a short bill in comparison to Black Tern. This is the second dark
White-winged Tern I have seen at this site now and both were juveniles in late
autumn/winter. The identification of this bird was made possible by taking some
poor photos, showing the benefit of having a camera when out birding.