Interesting thoughts Don, I never cease to be amazed by the site fidelity of
migratory birds!
Reading OBP bands certainly is difficult on the mainland! Takes much dedication
and lots of time - many days sometimes.
A number of dedicated volunteers (and some staff when there’s money to employ
people) do it though and from the bands we have recorded we do know that OBPs
can certainly be very highly site faithful. A number of birds observed at the
Western Treatment Plant have returned to the exact same patch (a mere few
hectares or so) year after year (5 years in one individuals case; see
http://birdsaustralia.com.au/images/stories/current-projects/obp/TUC_Jul09.pdf).
So yes they so use specific sites; but that’s only half the story. OBPs are
basically nomads (when wintering) their preferred habitats are highly patchy
spatially and temporally (i.e. when they seed). They may stay at one site for a
month or maybe a bit longer, but often they are often at a given spot only for
a matter of days before they move onto another, then another etc. How many
sites a given bird needs in a year we don’t know, but we’ve never identified
the same banded bird at more than 1 wintering site in a given year (I think…).
They clearly need multiple sites during the course of their wintering period.
There’s actually not a lot really good habitat around given how highly
specialised they
(http://birdsaustralia.com.au/images/stories/current-projects/obp/Potential-occurrence-Maps.pdf),
particularly not in recent years with the almost total loss of the western
quarter of their range in the Coorong and Lower Lakes.
To me training them is not really the answer, they are probably very good at
finding suitable habitat themselves, we just need to provide them with enough
to find. How much is the huge question, we have good habitat models now which
is a good start, but it’s still a big question given temporal variability -
just like it is for blossom nomads e.g. Swift Parrots.
Feeding stations have been used on the mainland, but that’s been mainly to get
the birds in a position where we can read bands, unlikely it would have a
behavioural effect I reckon.
Interesting to know about the Cranes. Managing just where a bird goes and not
the rest of it’s range is a gamble though. In the mid-1990s OBPs up and left
many of their traditionally important sites, in some cases sites where 20-40
bird flocks had been common were abandoned within a few years! (see Wingspan
Sept 2008 p18-23). With climate change of course it’s probable that will happen
with many habitat specialists.
There’s a project just underway to look at that broadly - “Adaptation
strategies for Australian birds” http://www.nccarf.edu.au/ARGP-tb .
________________________________
From: Peter Shute <>
To: "" <>; ""
<>
Sent: Saturday, 22 October 2011 7:21 PM
Subject: Re: [Birding-Aus] Orange-bellied Parrot and specific winter feeding
grounds
They seem to frequent the same areas each year, those that are found, but I've
no idea if they're the same individuals.
They're so strewn along the coast that most are unaccounted for. Unlike a bird
the size of a crane, they're a bit hard to find, and even harder to identify
individuals.
I think feeding stations are being tried, but I have no idea how successfully.
Peter Shute
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