Thursday, February 13, 2020

Dark-throated - Black-throated - Red-throated Thrush

Back in the day there was a Dark-throated Thrush. Its scientific name was Turdus ruficollis. There was only one species of Dark-throated Thrush. It bred in western and central Siberia, western Mongolia and north-west China. It was a migratory species moving south in the autumn to winter from Iran east to Kazakhstan, through northern India to southern China and northern Burma. But here's the rub: the Dark-throated Thrush was comprised of two very distinct races; one in western Siberia named Black-throated Thrush and the other in south-central Siberia named Red-throated Thrush. However, there are areas where these two races overlap and here intermediates occur.
At some point in the past decade, and I don't know when, these two races of Dark-throated Thrush were 'promoted' to full specific status. The Dark-throated Thrush was no more. It was now Black-throated Thrush Turdus atrogularis and Red-throated Thrush Turdus ruficollis.The two 'new' species are easily separated in the field. The Black-throated has grey upperparts, a black face and chest with the rest of the underparts being off-white whereas the Red-throated has a reddish-chestnut face and chest and also the outer tail feathers are a rufous-red. The tail of a Black-throated Thrush is all dark and does not display any rufous or reddish tones.
So what do you have in front of you when a bird shows the black face and chest of a Black-throated Thrush but also shows, quite clearly, chestnut-red in the outer tail feathers? The conclusion would be that it is an intergrade or hybrid between the two species. Back when there was just a Dark-throated Thrush - this would be it - no problem. Now it is different. Can you put a name to this bird? Is it a Red-throated or a Black-throated? Is it a hybrid and therefore not a full 'recognised' species and so it is a 'bird with no name'.
I look forward to see what the BBRC make of this!
In some of the following photographs, all taken of the bird in Grimsby on 12th February 2020, the rufous/chestnut in the outer tail feathers is quite visible.


These two shots of the bird perched in a tree clearly show the rufous-reddish tones to the outer tail feathers.








Black-throated x Red-throated Thrush Grimsby February 2020
For a 'pure' Black-throated Thrush the tail should be all dark with no hint of the rufous-red visible on this bird.


Sunday, February 2, 2020

Snow Bunting at Red Wharf Bay, Anglesey

Travelled over to Anglesey for a few days birding last week. The primary aim was to capture a few flight shots of Chough around South Stack. This proved to be a frustrating experience as the weather was ropey when the Choughs were flying. When the weather was fine the Choughs were nowhere in sight! I needed to overexpose by around a full-stop to get some definition on the black birds (both Chough and Raven) against white to grey skies. Doing this increased the ISO to an unacceptable level and by the time the photos were cropped to a suitable size the images were so degraded as to be almost useless.
Travelled  over to Red Wharf Bay for a lunchtime pint in the Ship Inn and was pleasantly surprised to find a Snow Bunting feeding along the harbour wall next to the car-park. No such exposure worries with this bird.






Snow Bunting Plectrophenax nivalis Red Wharf Bay, Anglesey 23rd January 2020