'Portlandica' Arctic Tern

The patch highlight of June so far was a 2cy Arctic Tern that spent a few days cruising around Baston Wader Pit mid-month, giving a great opportunity to study the so-called 'portlandica' plumage. In my ignorance I hadn't appreciated the origins of this rather broad-ranging, somewhat colloquial term and was fascinated to read that it stems from an initial misidentification by Robert Ridgway, who wrongly thought these immature birds to be a different species, which he called Sterna portlandica.

I seem to recall seeing one or two of these immatures in Arctic Tern colonies on previous occasions, and indeed they're not really all that scarce in some areas (see e.g. here), but I had never seen one locally. So, it was nice of this bird to appear at an otherwise quiet time of year, linger for a while and offer some fine views at times. A lovely bird to watch and one that was much more obvious at certain times than others. The classic buoyant 'looseness' of the flight style (compared to the slightly 'stiffer' action of Common), enhanced by the outer tail streamers, was particularly noticeable at times and some of the images below capture this quite nicely.

The photos were taken on two dates, with the first batch taken on the bright, sunny morning of 16th and the others a couple of days later, when it was overcast.

Arctic Tern, Baston & Langtoft Pits, 16 June 2022

Arctic Tern, Baston & Langtoft Pits, 18 June 2022