Thanks Sav,
I suspect it may not be that straightforward....In Australia I have
never seen a bird that was as pale as the two recent photographs (but
have seen a couple approaching this) and I have seen hundreds, probably
1000s, of Swamp Harriers here. In contrast, I've seen a few very pale
birds during just a handful of short visits to NZ. I'd suggest that pale
birds make up a larger proportion of the population in NZ rather than
these sightings simply reflecting a greater abundance there.
Two possible explanations for this might be that the NZ birds have come
through a genetic bottleneck when establishing that has led to a higher
proportion of the male population developing these plumages at a younger
age or alternatively perhaps the age structure of the NZ population is
different to the Australian population (i.e. birds live longer in NZ) -
quite possible given Swamp Harrier is effectively at the top of the
pecking order in NZ but a long way down the list in Australia.
Cheers,
Rohan
On 9/01/2011 9:09 AM, wrote:
In New Zealand - Swamp Harrier is the only large raptor, and
is very widespread and common. One can easily see up to 50
Harriers in a day. We see birds like this all the time, and
I believe that you Aussies don't see so many just because
there are not so many!!
Cheers
Sav Saville
Wrybill Birding Tours,NZ
"Great Birds, Real Birders"
----- Original Message Follows -----
Just for those that may be interested here is another
Swamp Harrier looking very similar to the bird pointed to
by Rohan.
http://www.pbase.com/palliser/image/131670089
This individual was photographed at Kurnell, Sydney in
November 2008. Such birds are not that uncommon, but
interesting just the same.
Cheers,
Tony
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Rohan Clarke
www.wildlifeimages.com.au
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