Olivaceous Elaenia? (1 Viewer)

[jocateme]

This bird has been seen near Araçatuba, São Paulo, in Southwestern Brazil. I'm thinking of an Olivaceous Elaenia (Elaenia mesoleuca), but I am not sure.
By the photos it is possible to see its tail had been cut (or is it a very short tail?), therefore it couldn't fly well (at least is what I think).
However, the Elaenias are distinguished by their wing bars, and the Yellow-bellied Elaenia (Elaenia flavogaster) has two wing bars with a third duller bar in the carpal joint, exactly like my bird does, but it has a crest, too, and this is why I am in some doubt about this bird. I thought of the Olivaceous espcially because it hasn't crest and is similar to the Yellow-bellied.
Any ideas?

Thanks for any help

 

[Rasmus Boegh]

Identification of Elaenias is notoriously unrealiable without voice. Also note that number of wing-bars not always is completely reliable in all species (contrary to the claims in several books). However, if I were to place an ID on this bird I'd say it looks most like a Small-billed Elaenia (E. parvirostris). The head is rounded, it appear rather olive above (and only extending slightly onto the chest-sides), the throat appear rather whitish-grey, the bill is dark with a pale base to the lower mandible, it has two clear and a third less distinct wing-bar (but this isn't a completely certain feature versus chilensis White-crested which is the race that occur in Brazil) and the eye-ring is quite prominent. So, clearly not a certain ID, but I'd still say Small-billed stands a fair chance of being correct. I guess you didn't try dividing the feathers on the top of the head to see if it had a concealed white coronal-stripe/patch.

 

[Rasmus Boegh]

Also, did you notice the colour of the lower mid-belly? It's whitish in White-crested & Small-billed, but dull yellowish in Lesser (and also in Plain-crested & Yellow-bellied, although it doesn't look like these two in my opinion). In any case the strenght of the eye-ring would still favour White-crested & Small-billed (the eye-ring of the Lesser usually, but not always, is narrower and less contrasting) and of those I'd still favour Smal-billed due to the wing-bars.

 

[jocateme]

My doubt about this bird was about the absence of the crest and, unfortunately, I didn't divide the feathers on the top of its head.
At the beginning I thought it could be a juvenile Small-billed or White-crested Elaenia, but I couldn't see any photo of them. What do you think about the absence of the crest?

 

[Rasmus Boegh]

At the beginning I thought it could be a juvenile Small-billed or White-crested Elaenia, but I couldn't see any photo of them. What do you think about the absence of the crest?

I think the seemingly complete absence of a crest almost certainly excludes Yellow-bellied & Plain-crested (yes, they can lower their crest to appear more round-headed, but I don't remember ever seeing one with such a flat head). The remaining species mentioned often appear like this when it comes to crest (White-crested often appear slightly more crested, but can appear just as round-headed as Lesser, Olivaceous & Small-billed) and I don't see anything suggesting this being a juvenile. Also, the only Elaenias among the species mentioned in this thread that usually show such a distinct eye-ring are Small-billed and chilensis White-crested - it's usually less distinct in Lesser, Olivaceous and Yellow-bellied (but as in so many other features in Elaenias, this isn't a completely certain feature, just basic statistics). The same goes for the white in the crest. Basically, Yellow-bellied (a species which, btw, also is larger than the other species discussed in this thread), White-crested, Small-billed and Lesser always have white in the crown. However, it is occasionally concealed in Yellow-bellied & White-crested and often concealed in Small-billed & Lesser (i.e. when seen normally it often doesn't seem as if they have any white in the crown). Olivaceous occasionally show a few white feathers in the crown, but most completely lack white (the last species mentioned in this thread, the Plain-crested, always lacks white completely). The short notes by José Fernando Pacheco on this page may be useful, although I've pretty much covered the various issues (for obvious reasons I presume you read Portuguese):

http://www.ib.usp.br/ceo/imag_sons/dica_elae.htm

Beware, however, that the three white-bellied group (Small-billed; E. parvirostris, White-crested; E. albiceps and Olivaceous; E. mesoleuca) often can show a slight yellow tinge to the lower flanks and vent. This is why I specifically mentioned the MID-belly in the earlier post (they never appear yellow there). Note also, that while the number of wing-bars isn't as good as suggested in some literature, it still works to some extend (i.e. when a third wing-bar is present it is most likely a Small-billed - it's just not completely certain as Olivaceous & White-crested with three wing-bars do occur occasionally). So, for above mentioned reasons I'd still put my money on Small-billed, but to be absolutely certain the voice is needed (a significant problem is, however, that White-crested only sings during the breeding season, i.e. it doesn't sing when in Brazil!). Arthur Grosset's page (http://www.arthurgrosset.com/) has photos of several of the species mentioned in this post and there's a photo of a Small-billed in the BF database:

http://www.birdforum.net/bird_view.php?bid=7716

 

[jocateme]

The photo from BF database of the Small-billed Elaenia is very close to mine. What's more, some notes I've read in the link point totally the SB out, like those about the eye-ring, the belly and the wing bars (as you had already said).
Thanks very much for your help, Rasmus.
And if you let me ask you, how do you know so much about Brazilian birds?

 

[Rasmus Boegh]

And if you let me ask you, how do you know so much about Brazilian birds?

Been spending a fair deal of time in South America and hopefully will spend much more in that amazing continent (shortly starting again with Rondônia). Also had the luck of knowing a few good Neotropical Ornithologists to whom I owe a great deal (many of which have a knowledge that far surpasses any I will ever get) and having access to a museum with a fair number of Neotropical specimens helps too. Many Neotropical birders don't like Elaenias. However, the more you look the more you notice and the more fascinating they become...

 

[jocateme]

Fascinating!