White-bellied Parrot, Cristalino, Brazil (1 Viewer)

[arthurgrosset]

There was a small flock of White-bellied Parrots I managed to photograph from the tower at Cristalino Lodge, northern Mato Grosso.

The first point is that the yellow uppertail and yellow thighs suggest that this is the sub-species Pionites leucogaster xantharus but all my books suggest that it should be the nominate subspecies that is found in northern Mato Grosso. This would have a green uppertail and green thighs.

The second point is the dirty belly. I have yet to see a White-bellied Parrot with a clean white belly and these birds were dirtier than most. I wondered if they had been at a salt lick or similar. The birds feet are also very dirty. Or is it an immature plumage of some sort?

 

[kbheaton]

You've referred to the Lexicon of Parrots?

http://www.arndt-verlag.com/projekt/birds_3.cgi?Desc=E295.htm&Pic=295_1.JPG

Kathy
Houston TX

 

[arthurgrosset]

You've referred to the Lexicon of Parrots?

Kathy
Houston TX

Well I hadn't Kathy but it just repeats the identification features of the various sub-species and gives the distribution of the nominate subspecies as "... northern Brazil south of Amazonas (sic) in states of Para, northern Mato Grosso and eastern part of Amazonas." so it doesn't answer my original question but underlines that it seems to be a good question.

But thanks for the link. It's a while since I visited the Lexicon of Parrots.

 

[Rasmus Boegh]

Yes, it does look unusually dirty below, and could perhaps be a young adult, but it isn't an immature, which have fairly obvious blackish mottling to the crown region. I've occasionally heard claims of White-bellied X Black-headed in the wild, but suspect that most of these simply are misidentified imm. White-bellied:
http://www.birdbreeders.com/images/...a-e513-4bc8-98da-61384b916e4bIMGP1185 (2).jpg

For example, while Lexicon of Parrots (linked in post #2) often is far more accurate than the "standard books" when it comes to distributions of South American species (see e.g. Aratinga acuticaudata, http://www.arndt-verlag.com/projekt/birds_3.cgi?Desc=E221.htm&Pic=221_1.JPG, and Amazona ochrocephala, http://www.arndt-verlag.com/projekt/birds_3.cgi?Desc=E332.htm&Pic=332_1.JPG), it's not quite up to the task here, and one would have to seriously question claimed reports of White-bellied X Black-headed from Mato Grosso (!!!).

There are specimens of nominate from far NE Mato Grosso, but I'm not aware of any evidence that it should be this taxon throughout the state. It seems that many writers of bird books only rarely realize the size of the Brazilian states; the problem is even worse with Pará, where many apparently haven't realized that this state includes sections both north and south a major ecological boundary; the Amazon river. So, two specimens of taxon X doesn't necessarily mean it is this taxon throughout the state. Anyhow, nominate White-bellied intergrades with xanthurus from around Rio Xingu and westwards, and based on my experiance the change is complete at least around Cristalino, where all individuals I've seen appear pretty standard xanthurus to me. Same with individuals furter west in Mato Grosso. Of note that individuals I've seen in NE Bolivia (Noel Kempff Mercado & nearby) also resemble xanthurus, even if xanthomeria supposedly is the only Bolivian subspecies according to the "standard" quoted distributions. That said, I haven't actually had them in the hand to check if there were minor details of the plumage not visible under normal field conditions that suggested they were intergrades rather than pure xanthurus.

 

[arthurgrosset]

Rasmus,

Thanks for the benefit of your experience in this matter. It does make me wonder just how accurate subspecies distributions are in other species where the visual differences are negligible. At least in White-bellied Parrot the differences are fairly easy to see.

I think you are a bit harsh on some authors of bird books. Most of the good ones have done a lot of field work and I suspect that descriptions of distributions require to be too brief in many books.

 

[Rasmus Boegh]

I think you are a bit harsh on some authors of bird books. Most of the good ones have done a lot of field work and I suspect that descriptions of distributions require to be too brief in many books.

Just to be sure there are no misunderstandings, I should mention that my last comment primarily was aimed at the general check-lists and family guides; not field guides to individual countries/regions where the authors often are remakably accurate.

http://www.flickr.com/photos/ffroeschlin/1355854043/#comment72157602073000187

 

[ZanderII]

There are specimens of nominate from far NE Mato Grosso, but I'm not aware of any evidence that it should be this taxon throughout the state. It seems that many writers of bird books only rarely realize the size of the Brazilian states; the problem is even worse with Pará, where many apparently haven't realized that this state includes sections both north and south a major ecological boundary; the Amazon river. So, two specimens of taxon X doesn't necessarily mean it is this taxon throughout the state. Anyhow, nominate White-bellied intergrades with xanthurus from around Rio Xingu and westwards, and based on my experiance the change is complete at least around Cristalino, where all individuals I've seen appear pretty standard xanthurus to me. Same with individuals furter west in Mato Grosso. xanthurus.

Hi Arthur, Rasmus

Nominate leucogaster does intergrade with xanthurus west at least to the Rio Cristalino - note the green thighs on the lower bird of this mixed pair I photographed there a couple of years ago...

http://www.surfbirds.com/media/gallery_photos/200602090233442.jpg

That is old news anyway - Novaes (1981) knew as much; you'll be able to read more in the forthcoming revision of the Alta Floresta avifauna...

Alex

Novaes, F. C. 1981. A estrutura da espécie nos periquitos do género Pionites Heine (Psittacidae, Aves). Boletim Museu Paraense E. Goeldi (Zoologia) 106: 1-12.