Black-throated Thrush – Wild Beijing 北京自然

This winter (2024-2025) is a poor one for some species we consider to be staple winter visitors in Beijing. Thrush numbers are well down, waxwings are scarce and there are almost no high-elevation redstarts in their usual mountain haunts. Certainly at Lingshan the sea buckthorn crop, which usually sustains good numbers of thrushes and redstarts, is the worst I have seen. Not only have few shrubs produced berries this year but those fruit that were gleaming orange at the beginning of autumn are now anaemic and shrivelled. This is most likely due to the fact that the autumn was wetter and milder than usual which seems to have resulted in most of the fruit succumbing to rot and fungi.

Sea buckthorn berries at Lingshan this winter (January 2025). Most seem to have rotted in the late autumn period, which was unusually mild and wet.

The best ‘thrush-watching’ this winter has been in the city parks, especially at drinking spots. Beijing is generally cold and very dry in winter, so after any juicy berries have been exhausted, winter birds tend to feed more on the drier fruits of cypress trees or similar, requiring them to drink frequently. Finding a spot close to a food source with running water and some cover is the best way to secure good views.

Of the four regular ‘winter thrushes’ in Beijing, Naumann’s (Turdus naumanni 红尾鸫 Hóng wěi dōng) is the most common in lowland Beijing, followed by Red-throated (Turdus ruficollis 赤颈鸫 Chì jǐng dōng), Dusky (Turdus eunomus 斑鸫 Bān dōng) and the scarce Black-throated (Turdus atrogularis 黑颈鸫 Hēi jǐng dōng) in order of abundance. In the mountains, the top two are reversed, with Red-throated the most abundant, followed by Naumann’s, Dusky and Black-throated.

This winter I have spent a bit of time at two regular spots for winter thrushes – Beihai Park and the Botanical Gardens. Although numbers have been relatively low, there has still been a reasonable variety, with some interesting mixes of genes on display. In Beijing it is common to see intergrades, most often between Naumann’s and Dusky and occasionally with the other species. However, as Beijing is a wintering area for these thrushes, we have no way of knowing the true parentage of any individual bird and thus we can only make educated guesses as to the origins based on visible plumage details.

Here are a few images, mostly from this winter, with some comments. As always, comments and corrections are welcome.

First up, some standard Naumann’s Thrushes (Turdus naumanni 红尾鸫 Hóng wěi dōng)

Naumann’s Thrush Turdus naumanni 红尾鸫 Hóng wěi dōng

8 January 2025, Beihai Park

28 January 2025, Botanical Gardens

These birds show the classic strongly marked underparts, including undertail coverts and golden-orange fringes to the wing coverts and mantle. I speculate that the bird in the second image is likely a female based on off-white supercilium and dark spotting on throat sides.

Red-throated Thrush Turdus ruficollis 赤颈鸫 Chì jǐng dōng

28 January 2025, Botanical Gardens

8 January 2025, Beihai Park

Note the much plainer upperparts, lacking the golden fringes, plainer face and relatively plain underparts, including the undertail coverts.

Dusky Thrush Turdus eunomus 斑鸫 Bān dōng

8 January 2025, Beihai Park

Note black crescents on the underparts, as well as rufous on the wings, dark tail and broad, long white supercilium.

Black-throated Thrush Turdus atrogularis 黑颈鸫 Hēi jǐng dōng

I have very few images of Black-throated Thrush Turdus atrogularis 黑颈鸫 Hēi jǐng dōng from Beijing, reflecting the relative scarcity of this species in the capital.

This one from Peking University campus in January 2013.

Intergrades

The following images are of birds that show signs of intergradation. I have added some comments to each and welcome opinions.

Dusky x Naumann’s

By far the most common intergrade in Beijing.

8 January 2025, Beihai Park

This bird is presumably a Dusky x Naumann’s intergrade, showing a mixture of blackish and reddish underpart markings, a long, broad dusky-like supercilium and Naumann’s-like mantle and scapulars.

28 January 2025, Botanical Gardens

This bird looks Dusky-like on first glance but on closer inspection shows prominent reddish markings on the underparts and undertail coverts, most likely evidence of some Naumann’s genes.

5 February 2025, Botanical Gardens

The two above could easily pass for Dusky Thrushes on first glance but, again, close inspection in particular of the second image, reveals reddish markings on the undertail coverts.

Black-throated x Red-throated

5 February 2025, Botanical Gardens

With a mixture of red and black feathers on the upper breast, this is presumably a Red-throated x Black-throated.

5 February 2025, Botanical Gardens

Whilst some dark markings on the throat and upper breast can be indicative of young or female birds, this bird shows some black feathers mixed with red on the lower part of the gorget, suggesting intergradation.

5 February 2025, Botanical Gardens

This bird shows darker red feathers than usual. Is this an intergrade with Black-throated or just a variation in Red-throated?

5 February 2025

This bird shows predominantly blackish feathers on the gorget but the undertail and undertail coverts are reddish, ruling out a pure Black-throated. The rather heavy marks on the undertail coverts may be indicative of Naumann’s genes.

Black-throated x Naumann’s?

28 January 2025, Botanical Gardens

This striking bird is wintering in the Botanical Gardens and is presumably a Black-throated x Naumann’s intergrade. The obvious black upper breast pattern combined with the Naumann’s like flanks and tail suggest this combination.

5 February 2025, Botanical Gardens

Two more images of the same bird showing the flank pattern and undertail coverts.

Red-throated x Naumann’s?

25 December 2021, Botanical Gardens

The denisty of red on the upper breast of this bird, combined with the relatively plain head pattern, may indicate Red-throated genes, while the flanks and reddish panel on the wing suggest Naumann’s.

Red-throated x Dusky?

The images below are from Beihai Park in January 2021. If only the head and breast pattern are considered, my best guess would be a Red-throated x Black-throated Thrush but the rufous wings suggest Dusky or Naumann’s influence. A Red-throated x Dusky may make most sense here.

18 January, 2021, Beihai Park

18 January 2021, Beihai Park

First generation intergrades are probably, in most cases, relatively easy to work out but there must be all sorts of combinations of second and third generation birds, and beyond, out there.

Watching winter thrushes in Beijing is always rewarding. Whether pure or intergrades, the majority are striking birds and a joy to spend time with, even if sometimes we can’t know for sure what we are looking at!

In Beijing in winter we are blessed with good numbers of East Asian thrushes… In my experience NAUMANN’S (Turdus naumanni) is the most common, followed by RED-THROATED (Turdus ruficollis) and DUSKY (Turdus eunomus) with BLACK-THROATED (Turdus atrogularis) being the most scarce. It is not uncommon to encounter intergrades, and birds exhibiting features of both NAUMANN’S and DUSKY are frequently encountered (see images at the end of this post). It is much less common to find birds showing features of both Red-throated and Black-throated. However, that is exactly what I found on Sunday at Lingshan.

An apparent adult RED-THROATED x BLACK-THROATED THRUSH, Lingshan, 1 March 2015. Note the presence of both black and reddish feathers on the throat/upper breast.

Unfortunately I wasn’t able to capture many (any!) good quality photographs but the two I did manage (above) show the unusually-marked throat and upper breast. A ‘pure’ Red-throated should show reddish orange marks only on the throat and breast with no black. And Black-throated should show only black or grey markings here, lacking any reddish tones. This bird clearly shows a mixture, with black dominating the lower part of the throat-patch and red dominating the upper part and the neck surrounds. I have never seen a bird like this before but it seems reasonable to assume that this is an intergrade between RED-THROATED and BLACK-THROATED. Although Red x Black-throated Thrushes are rare in Beijing, they are fairly frequent in Central Asia – see here for some information from Kazakhstan.

Vagrant East Asian thrushes, especially first year birds, still cause some identification problems in Europe (e.g. the 2013 Dusky Thrush at Margate in the UK and the recent putative Red-throated Thrush in Finland). This is because we don’t know for sure the variability of ‘pure’ birds, complicated by the fact that we know they interbreed. If we are to improve our knowledge, studies must be made on the breeding grounds, away from areas of potential interbreeding, so that we can better understand natural variation of pure species and pin down the tell-tale signs of intergradation. Although birders in Beijing and East Asia have a lot of experience of these thrushes, because we see these birds on the wintering grounds, in some cases we cannot be certain whether or not we are looking at pure birds or intergrades.. This means we are not best-placed to provide anything other than opinions about what we *think* are signs of intergradation based on seeing hundreds, and in some cases, thousands of these beautiful thrushes.

That said, I think we can all agree that the Lingshan bird is an intergrade. And what a cracker it was!

Just for interest, here are a couple of apparent DUSKY x NAUMANN’S THRUSHES from Beijing.

Tag: Black-throated Thrush

Winter thrushes in Beijing

Red-throated x Black-throated Thrush