Hi everyone
The latest Birdline listing leads me to raise this question. Corellas are now
fairly "regularly" seen in Sydney and environs/east coast, i.e. outside their
normal range. 12 or 15 years ago the sightings were much rarer and were
always treated as cage escapees or real strays or vagrants, but the sightings
outside their range are now being reported more and more often and surely they
can't all be cage escapees. One would presume by now that small breeding
colonies of Corellas are being established outside their "normal" range.
How long will it be before the accepted range of corellas is acknowledged to
have expanded or changed? What are the factors? Do they have to have bred
for xx years? Does the number of sightings have to increased to xx birds per
year for some consecutive number of years.
The RAOU categorises a bird as extinct if there have been no confirmed
sightings for more than 50 years. Whilst partially artificial in some ways,
it does at least provide a rule than can be followed and understood. Does the
RAOU or other official birding bodies have any such rules for extension of
range as above.
Are there any book publishers out there? If Slater, Simpson and Day, Pizzey
etc. were updating their field guides, would they show a wider range for
corellas yet?
Thanks
Irene Denton
Sydney NSW
Australia
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