Hi Peter
Yes, I do mean when saying "significant graduations of the tail tips on the
underside", that each layer of folded tail feathers is shorter than the next, &
yes to a greater degree than this shows in Leaden.
This is most obvious when the tail is closed - the tips of the outer 2 pairs of
retrices are especially very widely spaced. When the tail is spread it shows as
being very rounded, & even slightly fanned at times, as the outer 2 pairs of
retrices in Broad-billeds are noticeably shorter than the rest. In Leaden, all
tips of retrices are closely bunched, so only appear slightly graduated. These
tips can obviously only be seen on the undersiade of the tail.
I first read about this in Graeme Chapman's excellent article in Wingspan (vol
12, no 2, June 2003). I'm pretty certain that it was he that first recognised
this character as being typical of Broad-billeds v's Leadens. This article is
well worth searching for to read. His photos used for the article including the
Wingspan cover, also illustrate this well.
This difference in tail structure is also well explained & illustrated in
HANZAB.
Having seen a great deal of both species in the field, in my observations this
feature is an excellent way to discern these 2 tricky species.
I don't have access to S&D 's 7th edition, but if the images & text are
unchanged from their 5th edition, then the graduations are not depicted
accurately. The juv's graduations look inaccurate in 5th edition also.
I hope this explains better what I was referring to earlier.
Cheers
Martin Cachard
Cairns
0428 782 808
> From:
> To: ; ;
> Date: Sat, 9 Jul 2011 19:43:20 +1000
> Subject: Re: [Birding-Aus] Birding with a bubs in FNQ. Leaden Flycathcr at
> Redden Is, not a Broad-billed.
>
> Martin, can you please explain "significant graduations of the tail tips on
> the underside"? Do you mean that each layer of folded tail feathers is
> shorter than the next, and to a greater degree than in a Leaden Flycatcher?
>
> If so, this is shown in the illustration in S&D (p239, 7th edition). If you
> have that guide, does that picture look accurate?
>
> There's also a juvenile Leaden Flycatcher shown of the same page with similar
> graduations.
>
> Peter Shute
>
>
> --------------------------
> Sent using BlackBerry
>
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