Chiang Mai Prinias (1 Viewer)

[Danielibero]

Hi!!! I have this pics of Prinias from my travell to Thailand (in December 2019) that I identified, all of them, as Gray-breasted Prinias. However, seeing them now I think they can´t be them because of the the thick beak and the larges eyebrows. So I tried to ID them by myself, but I only can say that are not GBP, Hill Prinias or Yellow-bellied Prinias... So they could be Brown, Rufescent or Plain Prinias, according to the sightings recordings in eBird to Chiang Mai. If I have to say something, I would say that the first four pics are Brown, and the last Rufescent... but I far to be sure. Besides, I can't remember if the bird in the pic four is the same than in te first 3.

All the pics where taken in the same place: Reeds and bushes near to a field of rice, in the mencionated province.





I hope you can help me. Thanks in advance.

 

[andyb39]

All Plain Prinia IMO. The first four images show birds in the non-breeding plumage of the race extensicauda, in which the supercilium becomes reduced and the underparts take on a warm buff tone. They are sometimes mistaken for Yellow-bellied Prinia in this plumage.

I don't think the bird in the top image is as large-billed as it appears to be, as the same individual appears in the second image and has the slim dark bill of Plain Prinia.

Rufescent is an upland species and would not be found in this kind of habitat. Brown has been split three ways and birds occurring in this part of Thailand have been reclassified as Deignan's Prinia, Prinia polychroa.

 

[Grahame Walbridge]

All Plain Prinia IMO. The first four images show birds in the non-breeding plumage of the race extensicauda, in which the supercilium becomes reduced and the underparts take on a warm buff tone. They are sometimes mistaken for Yellow-bellied Prinia in this plumage.

I don't think the bird in the top image is as large-billed as it appears to be, as the same individual appears in the second image and has the slim dark bill of Plain Prinia.

Rufescent is an upland species and would not be found in this kind of habitat. Brown has been split three ways and birds occurring in this part of Thailand have been reclassified as Deignan's Prinia, Prinia polychroa.

Just to correct on the ssp. Andy, its blanfordi in NW Thailand and herberti elsewhere in the country, while the range of extensicauda in S China to N Laos, N Vietnam and Hainan.

Grahame

 

[andyb39]

Just to correct on the ssp. Andy, its blanfordi in NW Thailand and herberti elsewhere in the country, while the range of extensicauda in S China to N Laos, N Vietnam and Hainan.

Grahame

Ah, OK. This is where I really miss the free version of HBW. So the non-breeding plumage of blanfordi looks similar?

 

[Grahame Walbridge]

Ah, OK. This is where I really miss the free version of HBW. So the non-breeding plumage of blanfordi looks similar?

Similar, but not as saturated warm tones overall, throat and breast usually somewhat paler.
https://macaulaylibrary.org/asset/2...36.525019114.1612173147-2021484583.1612173147
https://macaulaylibrary.org/asset/2...11.525019114.1612173147-2021484583.1612173147

And I now thinking the lower bird looks better for w.pl Grey-breasted though the angle isn't the best
https://macaulaylibrary.org/asset/1...37.525019114.1612173147-2021484583.1612173147

Grahame

 

[johnallcock]

All Plain Prinia IMO. The first four images show birds in the non-breeding plumage of the race extensicauda, in which the supercilium becomes reduced and the underparts take on a warm buff tone. They are sometimes mistaken for Yellow-bellied Prinia in this plumage.

Extensicauda doesn't have a clearly distinct non-breeding plumage. They look essentially the same all year, except have a blacker bill when breeding (especially males). They're pretty distinct from Yellow-bellied on structure (deep-based bill) and plumage (less contrasting, uniform buff plumage).

And I now thinking the lower bird looks better for w.pl Grey-breasted though the angle isn't the best
https://macaulaylibrary.org/asset/1...37.525019114.1612173147-2021484583.1612173147

I'm sure this last bird isn't a Plain like the others - white supercilium before eye, grey head, rufous wings and slim, black bill. I agree that Grey-breasted is probably the best fit

 

[andyb39]

Extensicauda doesn't have a clearly distinct non-breeding plumage. They look essentially the same all year, except have a blacker bill when breeding (especially males). They're pretty distinct from Yellow-bellied on structure (deep-based bill) and plumage (less contrasting, uniform buff plumage).

Interesting - that's contra Robson, which clearly states that extensicauda and blanfordi have a non-breeding plumage, with "warmer upperparts, tail and wings" and "mostly rich buff underparts and supercilium", extensicauda being "deepest buff below". Apparently the tail is longer in this plumage too.

The bird in this link, photographed in Hanoi, fits the description above and is labelled non-breeding:

Chiền chiện bụng hung / Plain prinia

Chiền chiện bụng hung (ngoài mùa sinh sản) / Plain prinia (non-breeding season), Hà Nội, 2/2022 Mô tả: Chiền chiện bụng hung là một loài chim nhỏ trong họ chiền chiện (khoảng 13 cm). Chim dễ nhận r…

vietnamwildlife.org

I made the comment about the danger of passing off these individuals as Yellow-bellied as I met a Vietnamese birder online, who said he'd been doing this for years! I'm attaching a photograph of his (I don't know the date). Dramatically different from other races.

 

[johnallcock]

Fortunately extensicauda is resident here in Hong Kong, so it's easy to get familiar with the plumages. And Yellow-bellied is the main confusion species, so you quickly learn how to separate them if you're birding here. In fact, I'm always thrown slightly on these threads when I see you or Grahame highlight extensicauda as a source of ID confusion because this is how I think of Plain.

I was perhaps a bit too forthright with my comment previously. Non-breeding birds are more buff below and in the breeding season birds can look paler. I've always put that down more to wear/bleaching rather than a distinct plumage, and I think they fade over the course of the summer before moulting into a fresh buff plumage in autumn. The seasonal difference is not as pronounced as the difference between breeding and non-breeding Yellow-bellied (or some other species). The tail length does differ slightly, as in other prinias.
Breeding: http://www.hkbws.org.hk/BBS/viewthread.php?tid=5841&highlight=plain+prinia http://www.hkbws.org.hk/BBS/viewthread.php?tid=26172&highlight=plain+prinia
Non-breeding: http://www.hkbws.org.hk/BBS/viewthread.php?tid=20625&highlight=plain+prinia http://www.hkbws.org.hk/BBS/viewthread.php?tid=28783&highlight=plain+prinia

The juveniles contrast more than the adults, and are often quite white below: http://www.hkbws.org.hk/BBS/viewthread.php?tid=21482&highlight=plain+prinia http://www.hkbws.org.hk/BBS/viewthread.php?tid=14403&highlight=plain+prinia

 

[Danielibero]

Thanks you so much guys for all the information!! Then I leave the last bird as Grey-breated and the others I will change them to Plain. Interesting because they where all in the same flock, I want remeber. Is it usual to find different species of Prinias together?