Hi again,
That's an interesting line of thought. After some thought, I asked
myself: if some birds have down-curved bills, and some have upcurved
bills, would there be any greater disadvantage to having a side-curved
bill? Perhaps they are all in a similar boat, except, as you point out
Sav, in the case of the Wrybill, the advantage is at the breeding
grounds.
Jill
Jill Dening
Sunshine Coast, Queensland, Australia
26° 51' 41"S 152° 56' 00"E
Sav Saville wrote:
Hi all,
Just to throw the cat among the pigeons a little....
Here in New Zealand, Wrybills are bill-adapted for the breeding grounds
(where they forage for larvae around pebbles in braided river beds) and
certainly not for their wintering estuarine habitat where the bent bill is
presumably a disadvantage.
Cheers,
Sav Saville
Wrybill Birding Tours, NZ
"Great birds, real birders"
24 Puketiro Drive
Feilding
New Zealand
+64 6 323 1441
m("wrybill-tours.com","sav");">
www.wrybill-tours.com
-----Original Message-----
From: m("vicnet.net.au","birding-aus-bounces");">
[m("vicnet.net.au","birding-aus-bounces");">] On Behalf Of L&L Knight
Sent: 01 October 2008 01:01
To: Jill Dening
Cc: birding-aus
Subject: Waders, their bills, on the breeding grounds
I'll rephrase my answer. Why treat waders as a homogenous group? Is
it likely that a tendency that applies to plovers is likely to apply
to phalaropes, tattlers, knots, godwits, stints, sandpipers and stilts
as well? The degree of divergence between breeding and wintering
grounds will vary widely.
Perhaps you should distinguish between waders with highly specialised
bills and waders with generalist bills. You have already made an
implied distinction between migratory waders and non-migratory
waders. I suspect you have also distinguished between short distance
migrants [like Double-Banded Plovers] and inter-hemispherical migrants.
LK
On 30/09/2008, at 9:08 PM, Jill Dening wrote:
Yes, I know that, Laurie, but it doesn't help me to answer the
question. In fact that's why the question was asked in the first
place. It may be as Bruce thinks, that the bill length is only
advantageous in the wintering grounds.
A further question might be: I wonder if any of the bill lengths
pose a restriction on the breeding grounds? I could imagine a bill
as long as that of the Eastern Curlew might limit how prey can be
taken, if probing is not the manner of feeding. And I have the
strong impression that food is taken quite differently (from
probing) on the breeding grounds.
Cheers,
Jill
Jill Dening
Sunshine Coast, Queensland, Australia
26° 51' 41"S 152° 56' 00"E
L&L Knight wrote:
The breeding grounds vary somewhat between species. Some breed in
the tundra or on mountain ridges - environments that are nothing
like the habitats they winter in down here.
Regards, Laurie.
On 30/09/2008, at 7:59 PM, Jill Dening wrote:
Hi All,
I was recently asked a question about waders which totally fazed
me. I was asked if the length of the bill of different species of
wader is of any advantage on the breeding grounds.
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