Tuesday, July 31, 2018

Afsluitdijk - Black Tern arrival

Without doubt the greatest news was the birth of our son Siebren a month ago, but I will stick to birds here:-)
I drive the Afsluitdijk almost daily for work and last days it was obvious that Black Terns are arriving. A large part of the European population gathers along IJsselmeer/Afsluitdijk after breeding (and before they migrate South), and today I took my bike for a closer inspection. Highest numbers were present between Breezanddijk and Den Oever.
Black Terns above the Afsluitdijk (statue of Lely in the background)
The terns were feeding low on insects before the weather cleared and soon I found what I was looking for; a fine adult White-winged Tern!

Although the tern was already moulting towards winter plumage it was rather easy to pick out thanks to the pale upperwings and white rump.

From the underside it rather resembles a moulting Black Tern but note that the flight feathers are very pale (the primaries and secondaries).
And of course there were many Black Terns within photographic range. Below a juvenile, note the brownish back, dark spot on the breast-side and pale fringes along the coverts on the upperwing.