Saturday, 5 November 2016

'Dark-throated' Thrush

My uncharacteristic run of bad form continues, and it took an unexpected turn for the worse Saturday with a twitch to An Ma Shan for the 'Black-throated' Thrush Turdus atrogularis. I had been firmly intending to pick up this real mega this weekend, and with the offer of a lift there and back from Da Chaio Lin removing the need for faffing around on public transport, Saturday seemed like the day to go and get it (even though I would have been interested in staying up there overnight to have one final crack at Brown Wood Owl Strix leptogrammica had I ventured out on my own). Things looked far from promising when we arrived to 'negative news' of the bird early morning (and it would fail to show for the entire morning) and the only bird hopping around in range of my camera during the three hours spent waiting for it in the car park was a single Brambling Fringilla montifringilla (which found itself hotly pursued by an army of photographers).

At noon, I at least was having thoughts of throwing in the towel, but as I had seen a suspiciously promising-looking thrush fly over the car park mid-morning, I fancied that our target could still be in the area (especially as the bird was in the process of replacing its tail, and I had it down as a 'dead cert' on the strength of this alone). With dozens of photographers still hanging around the car park waiting, it seemed that if the bird did show it would certainly get seen, so I resolved to remain and began exploring the general area in the hope of simply finding myself enjoying a rare trip up into the mountains. A wander down a dark path did produce both a White-browed Bush Robin Tarsiger indicus and some kind of butterfly of interest to Da Chiao Lin, but otherwise the early afternoon only succeeded in compounding the misery that the morning had introduced.

I returned from my wanderings mid afternoon to find the photographers all sitting patiently in a line, focused on the spot that the Black-throated Thrush had been favouring. A quick look under the bushes in that area revealed a thrush to be sitting there, a thrush with a black-looking 'bib' on its upperbreast and a partially-grown tail! It appeared in the open shortly afterwards and the ominous cloud of dipping was instantly removed as the skies began to brighten in my perennially overcast mind. However, this moment was fleeting, as another black cloud rolled quickly in when I saw that much of the partially-grown tail was in fact red, meaning immediately that there was no way that this bird could be a (pure) Black-throated Thrush. I had seen few photos of this bird before setting off to twitch it, some of which had suggested traces of red in the throat and some of which (in better light) had not. As the tail had not been visible in any of the photos, I put the traces of red down to either a photo effect or the strong light that is common in the mountains (which I was happy with as an explanation, especially since no doubts about the bird's identity had been raised by the dozens of people that had already seen it). However, red was also clearly visible on the neck sides and in the supercilium of the actual bird, and, with the lower part of the bib being predominantly blackish, this could only mean that the bird was a hybrid (or second-generation hybrid, or 'intergrade', or even an aberrant Red-throated Thrush Turdus ruficollis as it had more features suggestive of that form than of atrogularis, just clearly not a Black-throated).

It was regardless a smart bird, but disappointingly one that could not be counted on any kind of list, including my current all-important year list. There was some nice compensation on offer for having made the long trip up into the middle of nowhere in the form of a relatively tame Formosan Muntjac Muntiacus reevesi which appeared at the visitors' centre late afternoon. Though this, the highlight of the trip, proved excellent fodder for my camera, it was just not a bird!

The only silver lining in all of this was that the weekend had presented me with a difficult choice of either twitching this thrush or heading north for one or two birds which had appeared late in the week up there. However, with the fine weather the island is currently experiencing, all of these birds had already departed Friday, so on balance a hybrid something is better than a 100% pure nothing! I am now very much ready for the next cold front. Above photos taken at An Ma Shan (Da Xue Shan), Taichung County 5/11/16.

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