This really is very nice work BUT ...
Will it work in Australian species? It might for some migratory waders or
even some forest passerines that have been demonstrated by banding to
return to the same site (Rufous Fantails, Spectacled Monarchs etc).
My understanding is that you can establish the site at which the birds
moult by looking at the chemical "signature" in their feathers. The trick
would be to then locate this cohort of birds on their "wintering" grounds.
Using Rufous Fantails as an example, this would require establishing
whether birds breeding (or more accurately moulting) in different areas
had different chemical signatures and then gathering feathers from birds
in their wintering grounds in northern Australia and PNG. Would the same
help unravel what is probably the much more complex movements of Grey
Fantails?
What about honeyeaters? This technique could shed light on the movements
of the two common migratory honeyeaters - Yellow-faced and White-naped.
These birds don't necessarily return to the same sites each winter, their
movements being affected by flowering patterns. The scale of movement
might, however, be relative - some populations migrating further than
others.
The problem, as I see it, is that the initial signature is gained at the
site where the birds moult. Australian passerines typically moult after
breeding. In Regent Honeyeaters, for example, this occurs at the time
when they have, often, departed the breeding site. It will all come down
to how precise the chemical signature is. Will all Regent Honeyeaters
moulting in the Capertee Valley have a similar chemical signature? Will
this differ from birds moulting in the Goulburn Valley, some 80 km to the
north (these could also be birds that bred in the Capertee Valley)? Does
it matter?
I suspect that this technique might work for birds that undertake long
distance migrations, such as Rufous Fantails but wonder how useful it will
be for other Australian birds. Our environment isn't as predictable as it
is for northern hemisphere birds and our birds have evolved accordingly.
Could well be worth someone looking into it though.
David Geering
David Geering
Regent Honeyeater Recovery Coordinator
NSW National Parks & Wildlife Service
P.O. Box 2111
Dubbo NSW 2830
Ph: 02 6883 5335 or Freecall 1800 621 056
Fax: 02 6884 9382
This message is intended for the addressee named and may contain
confidential information. If you are not the intended recipient, please
delete it and notify the sender. Views expressed in this message may be
those of the individual sender, and are not necessarily the views of the
NSW National Parks and Wildlife Service.
Birding-Aus is on the Web at
www.shc.melb.catholic.edu.au/home/birding/index.html
To unsubscribe from this mailing list, send the message
"unsubscribe birding-aus" (no quotes, no Subject line)
to
|
