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.

Saturday, 27 June 2015

The White-winged Black Tern at Swineham Gravel Pits

On the 2nd June 2015, a superb summer plumaged White-winged Black Tern was found at Swineham Gravel Pits. The bird stayed till 4th June, allowing many people to admire this beautiful bird.

It was initially aged as an adult and when I eventually caught up with it on 3rd June, my initial views questioned the ageing of this particular individual. On a constantly moving bird like this, in strong sunlight and the fact it was never really close, it's easy to see how a mistake could be made with the ageing of this bird. Thankfully, camera at hand, the still images allowed for the bird to be correctly aged as a 2nd-summer.

Note on the above images the primary pattern, which is strangely in moult. Don't know whether this is normal in 2nd-summers. Anyways, P10, 9 and 7 are old feathers, P8 has been replaced and P6 is being renewed. In adults only P10 and 9 and sometimes P8 should be old feathers. Note also the dark and rather scruffy outer secondary bar.

On the above two images, the latter © Peter Moore, note the scruffy rear edge to the black of the underwing, the brown tone to some of the black feathering and white/pale markings within the black, especially noticeable on the rear belly. Again signs of immaturity.

To compare, below are a few images of the stunning adult that was on Lodmoor in July 2013. 

Note the primary pattern, only P10 is old. Note also the lack of a bar on the outer secondaries.

Note the neat and tidy rear edge to the black of the underwing.

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