Con this is a vexed and ongoing issue.
To be blunt (and I may incur the wrath of some other COG members or database
people), I treat DY as meaning "dependent young", whatever that description
might entail, and do not restrict it to whether I actually saw food being
passed from parent to offspring. How would you treat a clearly dependent
offspring of a precocious bird (i.e. on that feeds itself from hatching, such
as Black-fronted Dotterel)?
As far as I'm concerned, the indicator of DY is to indicate that the bird is
dependent on a parent as a subset of categories of codes whose overall purpose
is to capture in the COG records that breeding has occurred. Without such an
interpretation, as you said, the database loses a lot of valuable information.
If DY was meant to indicate "seen being fed by parent" the code should have
been something else. That said, I do agree that the code DY should only be used
when a bird is clearly dependent on a parent, a decision which can still be
fairly subjective when the bird is IPDY or even IWDY.
My thoughts...
Harvey
Dr Harvey Perkins
CRC Programme Liaison Officer
Phone +61 2 6213 7472
Email:
-----Original Message-----
From: Con Boekel
Sent: Tuesday, 27 January 2015 4:49 PM
To: cog list
Subject: [canberrabirds] 'Dy or not dy?' that is the question.
Going for a constitutional this afternoon in BMNR, I noticed that there was a
young Noisy Friarbird begging noisily. The parent bird was busy feeding itself
and on four or five occasions found some prey and ingested it. Each time the
begging youngster approached the adult bird too closely and increased its
begging investment (more and louder calls) the adult bird would engage in some
sort of behaviour which clearly contained the message: 'Rack off'. So, not dy.
There was a similar scenario with two adult and one young Yellow-tailed Black
Cockatoo at JWNR two days ago. Again the adult bird, with a tasty morsel -
freshly hewn from its former home inside an acacia branch - lunged at the young
bird as if to say, 'Rack off!'. Not dy.
Then again, this afternoon, two Sacred Kingfisher youngsters in BMNR sat around
begging, apparently waiting to be fed. The parent was about, did not catch
anything with which to feed them and did not feed them. Not dy.
A group of three young Noisy Friarbirds along Upper David Street, the cultural
boundary between Turner and O'Connor, were all begging lustily.
But they were all also actively feeding on whatever is infesting the street
eucs, said infestation having attracted significant numbers of the usuals. Not
dy.
Also attracted to said infestation were two Red Wattlebirds. One of which was
feeding and the other of which was begging. No transfer of food occurred. Not
dy.
In a garden nearby, a young Magpie-lark was begging in the harsh and strangled
tones with which young Magpie-larks may signal that their voices are breaking.
Its companion was actively feeding itself but not the young bird. Not dy.
Four gardens along, a young Pied Currawong was begging (disconsolately, if one
wanted to be anthropomorphic about it) and not being fed. Not dy.
If COG had a breeding category 'IPDY' (Immediate Post Dependent Young) or
possibly even 'IWDY' (I Want to be a Dependent Young) I would have had many a
record to add to the COG database, including a rare breeding record for the
YTBC.
But alas, I came up with many an NDY instead.
*******************************************************************************************************
This is the email announcement and discussion list of the Canberra
Ornithologists Group.
Emails posted to the list that exceed 200 kB in size, including attachments,
will be rejected.
When subscribing or unsubscribing, please insert the word 'Subscribe' or
'Unsubscribe', as applicable, in the email's subject line.
List-Post: <>
List-Help: <>
List-Unsubscribe: <>
List-Subscribe: <>
List archive: <http://bioacoustics.cse.unsw.edu.au/archives/html/canberrabirds>
List manager: David McDonald, email <>
*************************************************************************
The information contained in this e-mail, and any attachments to it,
is intended for the use of the addressee and is confidential. If you
are not the intended recipient you must not use, disclose, read,
forward, copy or retain any of the information. If you received this
e-mail in error, please delete it and notify the sender by return
e-mail or telephone.
The Commonwealth does not warrant that any attachments are free
from viruses or any other defects. You assume all liability for any
loss, damage or other consequences which may arise from opening
or using the attachments.
The security of emails transmitted in an unencrypted environment
cannot be guaranteed. By forwarding or replying to this email, you
acknowledge and accept these risks.
*************************************************************************
|
