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Curve-billed Scythebill (1 Viewer)

ZanderII

Well-known member
Alan

"paraensis"

You determined for me to whittle away my evening?

The first cut of "paraensis" is certainly very unusual for a Tolmomyias - I was reminded of something and have just remembered the "song" of Todirostrum pictum, which is not dissimilar (though the notes are delivered at a faster pace). The second song is also unusual and sounds a little like a Myiarchus!

You are in good company in failing to perceive this as a Tolmomyias, the authors of the first Alta Floresta inventory (Zimmer et al. 1997) missed the species due to then unfamiliarity with the vocalisations - see discussion in Lees et al. (2013). This despite the fact that it is a nuclear canopy flock species present in virtually every assemblage.

If my recordings don't convince you compare them with:

http://macaulaylibrary.org/audio/126754
http://macaulaylibrary.org/audio/127414
http://macaulaylibrary.org/audio/115022
http://www.xeno-canto.org/18058
http://www.xeno-canto.org/94647

I think in the Cotinga article, it is suggested that the nominate form (or a bird with identical song) is also present, so assume this is the second taxa. I would guess the edaphic gradient is not a simple line so might these birds be locally sympatric anyway? I think the same happens with a large non-passerine, with two song types on different soils, that someone is supposed to be working on..

We assigned the birds south of Alta Floresta to the nominate (with the disclaimer that we didn't know what calamae sounded like), the soils are a mosaic and it is likely that both are in contact somewhere between the two nearest localities (c. 50km) over which there is no geographic barrier (Lees et al. 2008). So yes, there is an excellent chance they could be sympatric and likely to be behaving as BSc species given that their song types are well preserved on either side of this zone.
 
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ZanderII

Well-known member
definitely Green-backed (= Violaceous) Trogon

cheers, a

Think you are getting confused there...

Green-backed Trogon = (Trogon viridis) = former White-tailed Trogon south of the Amazon

Amazonian Trogon (Trogon ramonianus) = former Violaceous Trogon south of the Amazon

Its seems to be the former but I had forgotten to add it in (bearing in mind that the recording is a little distant and Trogons can fool the most seasoned Amazonian field ornithologist - I prefer to leave them out unless I'm sure). The Tolmomyias sings throughout so arguably dominates the cut.... ;)
 

lewis20126

Well-known member
Think you are getting confused there...

Green-backed Trogon = (Trogon viridis) = former White-tailed Trogon south of the Amazon

Amazonian Trogon (Trogon ramonianus) = former Violaceous Trogon south of the Amazon

Its seems to be the former but I had forgotten to add it in (bearing in mind that the recording is a little distant and Trogons can fool the most seasoned Amazonian field ornithologist - I prefer to leave them out unless I'm sure). The Tolmomyias sings throughout so arguably dominates the cut.... ;)

Of course, Green-backed(=White-tailed). I have never got used to the "new" names and luckily for me, I think Collar et al. are about to lump at least some of these Trogon splits in their new checklist!

cheers, a
 

lewis20126

Well-known member
Alan

If my recordings don't convince you compare them with:

http://macaulaylibrary.org/audio/126754
http://macaulaylibrary.org/audio/127414
http://macaulaylibrary.org/audio/115022
http://www.xeno-canto.org/18058
http://www.xeno-canto.org/94647

We assigned the birds south of Alta Floresta to the nominate (with the disclaimer that we didn't know what calamae sounded like), the soils are a mosaic and it is likely that both are in contact somewhere between the two nearest localities (c. 50km) over which there is no geographic barrier (Lees et al. 2008). So yes, there is an excellent chance they could be sympatric and likely to be behaving as BSc species given that their song types are well preserved on either side of this zone.

Quite a mixed bag of recordings there but yes, with the terminal flourish of what I see as the "normal" song clearly different from "nominate"; I'm not sure about the single note "dawn song" on the original cut (though I'm sure your identification is correct) . I normally think of dawn songs for most species and where they exist as distinct, as being much richer and more varied than day time songs? Of course this may be an exception with the Alta Floresta Yellow-margined Flycatcher. Make that SACC proposal 4 species!

BTW those White-chinned Woodcreepers are remarkable. There must be two species there - I'm sure even Nigel Collar would find a way of giving them the magic 7 if he opened that particular drawer, even if the vocals are not much help.

cheers, alan
 

ZanderII

Well-known member
I normally think of dawn songs for most species and where they exist as distinct, as being much richer and more varied than day time songs?

Maybe in the majority of cases, but several tyrant flycatchers have quite monotonous repetitive songs.

Of course this may be an exception with the Alta Floresta Yellow-margined Flycatcher. Make that SACC proposal 4 species!

Distribution occurs all the way east to the Atlantic, so maybe that vernacular name is a little inappropriate....
 

lewis20126

Well-known member
Distribution occurs all the way east to the Atlantic, so maybe that vernacular name is a little inappropriate....

Yes, there seems little sense in creating another Sandwich Tern. "Para" would presumably not be wholly ideal (wrt non-specialists at least) given the presence in Mato Grosso? I'll certainly be looking forward to the paper - which I'm sure Richard will provide a link to within minutes of its availability!

cheers, a
 

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