Black-throated Thrush (BBRC)

Black-throated Thrush Turdus atrogularis

Vagrant. Eastern European Russia to north-central Siberia, north-west Mongolia. 

                       Black-throated thrushes: left, Grimsby February 8th 2020 (Mark Johnson) and centre March 2020 (Graham Catley);

                                                     right, 2CY male found dead in Bailgate, Lincoln January 4th 2022 (Phil Hyde).

Two records of this handsome thrush, the first in January-February 2020, a 2CY male. An excellent find in suburban Grimsby frequenting a college green by a busy commuter road and finding plenty of earthworms to eat. This species has been regarded as conspecific with Red-throated Thrush, T. ruficollis, but has several very different phenotypic characters and considerable vocal differences; reports of mixed pairs are exceptional, and hybridization perhaps reduced by difference in timing of breeding. The second record was unfortunately found freshly dead on Bailgate in the centre of Lincoln January 4th 2022. The skin is in the British Natural History Museum. On dissection they reported that the bird appeared in excellent condition. It is presumed that the bird had flown into a window as there were no external signs at all of injury.

These thrushes breed in a variety of habitats: pure coniferous forests along rivers and streams, sparse dry woods, larch (Larix) clumps, semi-open willow (Salix) scrub, groves of poplar (Populus) and birch (Betula), buckthorn (Rhamnus) thickets and wooded bogs, to 2200 m. They depart from mid-Aug and winter from Iraq and Arabia across southern Asia. There have been 89 British records, 1950-2021. With seven previous records in Yorkshire, this was an overdue find, albeit not easy to do among the 1000s of commoner thrushes arriving on the coast every autumn.

Finder’s Report: Black Throated Thrush, Grimsby, 30th January-2nd April 2020, first county record.

by Josh Forrester.

Note: this account is based on the article which first appeared in Lincolnshire Bird Report 2020. The BBRC report for 2020 noted that this bird posed an interesting dilemma for the Committee. It showed a hint of warm brown to the basal edges of the outer tail feathers. Ordinarily, shades of red in the tail would point to hybrid influence by Red-throated T. ruficollis or even, more rarely, Naumann’s Thrush T. naumanni (see Brit. Birds 110: 116–121). However, BBRC felt that in this case – on a bird that was otherwise perfect for Black-throated Thrush and where the warm coloration at the base of the tail was neither particularly red nor particularly extensive – there was insufficient evidence for acceptance as a hybrid and the record therefore appears here as Black-throated Thrush.  

Circumstances and description 

I work at the Grimsby Institute and as I live close to work, I often walk home for lunch at midday. There is some open ground with a stand of trees on the south-eastern boundary of the college. In the winter I usually walk on the pavement around this area, but it had been dry, so at lunchtime on Jan 30th I decided to cut across the grass. About halfway across the grass, a thrush on the ground caught my eye. In the winter, this area plays host to the occasional ground feeding Mistle Thrush (Turdus viscivorus) and Song Thrush (Turdus philomelos), but it wasn’t either of these. Fieldfare (Turdus pilaris) briefly crossed my mind due to the colour and shape but something about this bird was different. When I first saw the thrush, it had its back to me and was feeding on worms amongst a group of Black-headed Gulls (Chroicocephalus ridibundus). It was strikingly pale underneath. I moved towards a tree to obscure myself somewhat and tried to move closer. The bird flew in to a tree but returned to the ground shortly thereafter and now it was facing me. The clear contrast between its black throat markings and its creamy, grey breast made me say aloud: Black-throated Thrush!

This species was never on my radar and certainly not something I would have expected in such a mundane place. There were two things that helped me make this identification:

1. My local patch is about a mile south-east (as the thrush flies*) of my workplace. Each year I spend time in the spring and autumn on the search for Ring Ouzel (Turdus torquatus) as well as counting passage Fieldfare, Redwing (Turdus iliacus) wintering Blackbirds (Turdus merula) and continental Song Thrushes. I’m quite familiar with the Turdidae of Grimsby.

2. A long-staying, adult male Black-throated Thrush had been present at Whipsnade Zoo in Bedfordshire since December 11th 2019. Photos of this bird had done the rounds on Twitter, so that was in my mind.

Although I was shaking with excitement, I managed to obtain some record shots and videos with my iPhone and then got in touch with some local birders. I received reassurance that it “looked good for Black-throated Thrush” and that it would be a first for Lincolnshire. Once I knew other birders were inbound, I went home to grab my binoculars and returned to meet with Chris Atkin and Howard Bunn. The bird spent a significant amount of time in the upper tree canopy and gave only brief views. Eventually it flew some distance away across Laceby Road and was observed to have a distinctive undulating flight-pattern associated with larger thrushes. Unfortunately, due to work obligations, I was unable to spend much more time that afternoon observing the thrush. I understand that it did return – providing reasonable views and photographic opportunities to those who had attended that afternoon. Graham Catley – the don of Lincolnshire birding – suggested that the bird was a 1st-winter male. The ensuing twitch over the weekend of 1st / 2nd of February (and the weeks following) provided ample opportunities for birders from near and far to connect with this obliging Siberian delight. It remained in the area until it was last sighted on April 2nd.

( *Sadly, I do not believe the thrush visited my patch during its regular perambulations of the area.)

Black-throated Thrush – some plumage features and analysis

During its stay, some observers commented on the warm brown colouration visible at the base of the tail in this bird. Graham Catley provided the analysis below highlighting the salient plumage features.

1. Crown, nape, mantle, and rump all mid-grey
2. Tertials, secondaries and primaries all blackish-grey with pale creamy fringes and edges to secondaries and tertials forming a pale wing panel.
3. Alula black with narrow pale fringe; primary coverts blackish with paler grey fringes; greater coverts of two ages, some are pale grey with creamy edges and other, newer ones are darker grey.
4. Tail feathers blackish-grey with a very faint and restricted hint of rufous at the base of the outermost feather on the right side of the bird, as here; on the left side this colouration was even less obvious.
5. Chin, throat, and upper breast all black-centred feathers with pale cream fringes.
6. Breast and belly creamy with diffuse pale grey streaks and markings along the flanks. Undertail coverts also creamy.
7. Note the rusty-orange underwing coverts, with the colour deeper on the median than lesser and greater coverts. The underside of the flight feathers are a very pale creamy colour.

During the consideration of this record, the presence of the warm brown colouration at the tail base was a point of contention. There was no other red colouration in the face or breast feathers and it can be surmised that this bird may have inherited some Red-throated Thrush T. ruficollis genes from a generation or two back, but this is speculation. Whatever the true picture is, in the light of current knowledge, the record was unanimously accepted as being of an immature (2CY) male. The record was accepted by BBRC (British Birds 114(10): 570-628). This constitutes the 403rd species to be added to the Lincolnshire list, a welcome addition given the county’s dearth of rare thrushes.

(Updated with reference to the new Birds of Lincolnshire (2021) December 2022)