Sunday, 19 May 2013


The circumstances of this bird's discovery and subsequent twitch bear several characteristics of the modern day scene. It was confirmed online from photographs for a start, when a local birder forwarded them to the info services. And it kicked off controversy on the web in its wake as 'Trial by Birdforum' grappled with the nature of its true identity, specifically how genetically 'pure' it was.

The first twitchable dusky thrush since 1959 (and potentially the tenth for Britain) was always going to prove popular, more so since the BOU split it a few years back. I hadn't actually realised it had been split until after I'd seen the bird! I heard of its presence belatedly when a catalogue of events left me in the dark until about 9.30am on the morning of the 18th, when news had actually gone out the previous evening at around 11.10pm. I wasted no time in making arrangements to get down there, travelling with a guy called Geoff (from Notts), James Hunter and Richard Thomas.

I saw the bird on arrival and despite its reluctance to go anywhere near the ground eventually had excellent views. There was a rolling crowd of perhaps 200-400 birders with well in excess of a thousand likely to have seen it throughout the day. To the chagrin of those who hadn't made it, it was gone the next. I returned home happy with not just the thrush under the belt but a nice female Monty's and a cattle egret to boot. But the thrush's arrival marked an influx of rarities and scarcities right down the east coast and those in the north-east especially had plenty more less rare species to go and see.

The uncertainty over the bird's genetic purity – due mainly to the overall lack of contrast, the warmth of the spotting on the shoulder and rear flanks and the rather paleness of the warmer colours found on the inner wing, mainly the secondaries – maks it not a not quite straightforward record and not disimilar to the situation regarding the Rainham slaty-backed gull. But my thoughts – as with that bird - are that it's likely to be within the variation of the claimed species, though it would be hard to completely rule out the possibility of introgression of naumanni genes down the line. Luckily most people seem reasonably happy with it now (including experts such as Lars Svennson) , just hope it passes the BBRC test!

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