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To
those (if any) who don't quite follow this, I will add a simplistic bit.
Curiously I find the word "apterium" relates to "without wings" but is not used
that way here, but to mean the parts of the bird's body that have gaps in the
feathers. Because in most birds feathers are not evenly distributed but are in
"tracts". Most (?) birds always have a gap of bare skin in the middle of the
abdomen (i.e. ventral apterium), although of course the surrounding feathers
usually cover this up. When brooding, this skin usually becomes swollen with
increased blood circulation to help the incubation. The question here is do or
don't cuckoos (that don't brood eggs), go through the same process. This is
bringing up different answers. No reason why the answer should always be
the same. Quite possibly they go through the same hormonal processes related to
egg laying.
It has
also raised the second question about whether presence of "brood patch" or
"gravid with eggs" can / should constitute a breeding record. I reckon they are
better evidence of likely breeding than some of our other accepted categories,
but probably not thought of at the time (20 years ago), as those doing the list
probably were not thinking in terms of experienced people actually handling the
birds.
Philip
Geoff's Cartoon
deleted for space..........
From: John
Brown [
Sent: Tuesday, 5 November 2013
6:01 PM
To:
Subject: RE:
[canberrabirds] Brood patches are evidentially found on Shining Bronze-Cuckoos
despite not being required
Naomi,
Interesting!
Thanks for finding and sharing that. It's a shame he doesn't provide any
references for his assertion that eye-witness accounts of brood patches are
mistaken identifications of the ventral apterium. I'm sure the eye-witnesses
disagree! Certainly those at New Chum Road recently do. I'll continue to see if
there is anything in the HANZAB that can
clarify this.
John
---
John
Brown
From: Naomi
Langmore
Sent: Sunday, 3 November 2013 9:10 PM
To:
Subject:
RE: [canberrabirds] Brood patches are evidentially found on Shining
Bronze-Cuckoos despite not being required
This
is an interesting topic! Here's a link to a paragraph in Payne's book about
cuckoos, in which he states that reported brood patches in cuckoos may actually
be the ventral apterium and that no brood parasitic cuckoos have brood
patches;
http://books.google.com.au/books?id=FX3dzcG-WoMC&pg=PA128&lpg=PA128&dq=do+all+nesting+birds+have+a+brood+patch&source=bl&ots=uTdN-c7zRS&sig=MVfxfxOIGF9m1kuEuLg-hyp_Fuo&hl=en&sa=X&ei=0B52UoXbCorukgXhhYH4Dw&ved=0CGUQ6AEwCTgK#v=onepage&q=do%20all%20nesting%20birds%20have%20a%20brood%20patch&f=false
cheers
Naomi
From: Mark
Clayton
Sent: Sunday, 3 November 2013 6:38
PM
To: 'Damien Farine';
Subject:
RE: [canberrabirds] Brood patches are evidentially found on Shining
Bronze-Cuckoos despite not being required
When
it come to some of the information on birds, and other topics, on Wikipedia, I
have often found mistakes in their data.
We
have had one Horsfield’s Bronze-Cuckoo (an adult bird) at Charcoal Tank with a
brood patch and I have seen bronze-cuckoos elsewhere with brood patches. The
majority of the banding team are now well versed in checking for brood patches
an all bird species and I often check to be certain. I know that the HB-C was
checked by me, and while it was not a full blown brood patch, it certainly was a
brood patch.
Mark
From: Damien Farine
Sent:
Sunday, 3 November 2013 6:08 PM
To:
Subject:
RE: [canberrabirds] Brood patches are evidentially found on Shining
Bronze-Cuckoos despite not being required
Perhaps before
concluding that Wikipedia is wrong, it might be worth verifying if the brood
patches are fully vascularized, or if they are just the loss of feathers around
the abdomen/vent. For example pulli/chicks have bare abdomens for some time,
even after fledging. It could simply be that the loss of these feathers is
linked to some hormonal change associated with breeding, but doesn't necessarily
mean that birds have a fully-operational brood patch.
Sorry - its been a
while between posts to canberrabirds - but I do still follow it
keenly.
Damien
From:
To: m("canberrabirds.org.au","canberrabirds");"
target=_blank>
Date: Sun, 3 Nov 2013
06:49:02 +0000
Subject: RE: [canberrabirds] Brood patches are evidentially
found on Shining Bronze-Cuckoos despite not being required
The wiki entry that
"Brood Parasitic Cuckoos do not develop brood patches" is clearly wrong, as
Shining Bronze-Cuckoos and Horsfield's are both brood parasites and do not
incubate their eggs, but have brood patches. If anyone knows how to correct it,
please do! … or before you know it we'll have government policy based on this
erroneous "wiki-fact"
John
From: Geoffrey Dabb
Sent: Sunday, 3 November
2013 5:39 PM
To:
Subject: FW:
[canberrabirds] Brood patches are evidentially found on Shining Bronze-Cuckoos
despite not being required
2 snips from
Wiki. Some cuckoos incubate their own eggs so issue might depend on how
close to those cuckoos is the relevant parasitic cuckoo
From: John Brown
Sent: Sunday, 3
November 2013 4:58 PM
To: 'COG_Mailing_List'
Subject:
[canberrabirds] Brood patches are evidentially found on Shining Bronze-Cuckoos
despite not being required
Just in case anyone
remembers Philip raising the excellent question about whether brood parasites
such as Shining Bronze-Cuckoos really form brood patches. Well, I don't have
ready access to HANZAB so It's a bit hard to check. However, the Bander's Aid
states brood patches found on Shining-Bronze-cuckoos, Horsfield's
Bronze-Cuckoos, and Black-eared Cuckoos at least. Apart from that I check with
the A-Class bander who banded the bird and he confirmed that the bird definitely
had a brood patch (i.e. there hadn't been a clerical error) and that he is "90%"
sure it was also gravid (pregnant with egg).
So despite getting
some other bird to brood on their eggs, it appears that the brood patch has
lingered on in these cuckoos, and hence that the characteristic has not been
extinguished by evolution in these species even though it is no longer required.
John
From: Philip Veerman
Sent: Wednesday, 30
October 2013 6:08 PM
To: John Brown;
'COG_Mailing_List'
Subject: Pilotbird breeding records?
Pilotbirds
are residents so surely they must breed here. The COG Atlas (now very old) has a
mention of one nest building from 1988. Presumably they are hard to find
breeding. I'm intrigued about "FYI, brood patches were also found on:
Shining Bronze-Cuckoo". Do brood parasites also form this? I would have thought
this feature would have been deleted over time.
-----Original Message-----From: John Brown Sent: Wednesday, 30
October 2013 4:59 PM To: COG_Mailing_List Subject: [canberrabirds] Pilotbird breeding records?
At New Chum Road mist
netting which happened to coincide with the Blitz, we netted a pilotbird with a
brood patch. There was some speculation about whether or not there were records
of pilotbirds breeding in the ACT?
FYI, brood patches
were also found on:
Shining
Bronze-cuckoo
White-browed
Scrubwren
Brown
Thornbill
Striated
Thornnbill
Eastern
Spinebill
Yellow-faced
Honeyeater
Crescent
Honeyeater
White-napped
Honeyeater
Golden
Whistler
Eastern Yellow
Robin
Bassian
Thrush
John
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