Hi,
The debate on Western Corella conservation is interesting. Is there any direct
evidence of eastern long-billed having a displacement impact?
The subspecies Cacatua pastinator pastinator (southern form) is listed as
"vulnerable" to extinction under the EPBC Act. I wonder why the other
subspecies isn't listed similarly given the restricted range and, according to
HANZAB, relatively low numbers. It may be because it was considered to be
increasing in the recent past. If this is still the case then perhaps it isn;t
a conservation priority. If however, the species is again declining, then it
may be an issue.
One thing worth bearing in mind with any bird dependent on agricultural zones
is that relatively small changes in farming practice can have significant
impacts. Coming from a country (England) that has seen declines of up to 95% in
25 years for otherwise common farmland birds, I am concerned that close
attention is paid to agricultural policy. Small shifts in farming incentives or
the introduction of new technology such as pesticides, can have a sudden and
dramatic macro-environmental impact. If eastern long-billed corella is taking a
foothold, this might be one of only a number of obvious potential pressures,
particularly if eastern long-billed is more capable of withstanding the impact
than the local species - not to mention the potential interspecific competition
posed by little corella which, according to HANZAB, has also expanded its
range. Both little corella and eastern long-billed are known to exploit
agricultural areas in the east and do quite successfully. I wonder if this is
enough evidence to suppose that the species are less susceptible to
agricultural intensification than western corella and would therefore, be
likely to outcompete it?
Regards,
Simon.
--
Simon Mustoe, Director
AES Applied Ecology Solutions Pty. Ltd
39 The Crescent
Belgrave Heights
Melbourne
Victoria 3160
AUSTRALIA
Tel +61 (0)3 9752 6398
Fax +61 (0)3 9754 6083
Mob 0405 220830
Email
This e-mail, including attachments if any, have originated from AES Applied
Ecology Solutions Pty. Ltd. and may contain information that is confidential,
or covered by legal professional privilege, and is intended for the named
recipient(s) only. If you have received this message in error, you are asked to
inform the sender as quickly as possible and delete this message and any copies
of this message from your computer system network.
==============================www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
=============================
|
