This blog is about my birding exploits, which mainly take place in the Weymouth/Portland area, in Dorset. Will also include stuff from elsewhere, plus some other critters too. Hope you enjoy. All photographs are © Brett Spencer, unless indicated otherwise. The above image is of a Siberian Rubythroat, taken in Holland in 2016.

Sunday, 18 May 2014

Arctic Tern

Well, he's back for yet another year with the Common Terns on Lodmoor. I'm not sure how many years he's been coming back, but although he has hybridized, albeit unsuccessfully, with Common Tern, he's yet to find one of his own kind. He has courted controversy, with some observers questioning it's identity, based on the perceived bill and legs being too long. It's bill is within the range of variation of that shown by Arctic Tern and it's leg length is sometimes judged incorrectly, as depending on the belly feathering, the legs can appear longer when the belly feathering is held flat against the body. When compared with the nearby Common Terns, it's legs are noticeably shorter. Plumage, structure and call are classic Arctic Tern. In fact, it's call is often a clue to it's presence within the Common Tern colony.

The Arctic Tern is to the left of the incubating Oystercatcher. Note the tail length, extent of grey on the underparts and primary pattern.

Arctic Tern to the right of the Common Terns. Note the long tail and much sleeker structure.



Note the thin black trailing edge to the primaries on the underwing.




Note the pattern of white on the cheek, which is like a stripe that borders the black cap.

A stunningly elegant bird.

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