Re: hawkesbury&sydney birds

Subject: Re: hawkesbury&sydney birds
Date: Tue, 25 May 2004 13:30:22 +1000

Keith Brandwood wrote "It appears to me that bird populations around Sydney are well down in numbers this autumn."

I think the reason is a simple as drought!  I appreciate that the coast is not as badly drought stricken as western NSW (it's raining in Dubbo!!!!!).  However, the fact that Sydney's water supplies are nearing record lows suggests that not all is well.

Drought affects flowering and seed set of plants, insect numbers as well as opening up of the structure of the forest as plants shed leaves or die.  The consequences are less resources (affecting breeding and survival) and, potentially leaving survivors open to greater predation rates.  

On predators - some prey items such as insects might be scarcer so they rely more on what is available.  Those birds that do attempt breed might suffer higher predation rates.

This may explain lower numbers of smaller birds but what about Keith's pigeons?  Wonga Pigeons are looking for Acacia seed.  Are they setting fruit in these drier conditions?  Brown Cuckoo-doves are looking for fruiting "rainforest" plants?  Are they stressed and therefore not setting fruit?

All food for thought.


David Geering
Regent Honeyeater Recovery Coordinator
Department of Environment & Conservation
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 notify the sender and then delete the message. Views expressed in this message may be those of the individual sender, and are not necessarily the views of the NSW Department of Environment and Conservation.
<Prev in Thread] Current Thread [Next in Thread>

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the birding-aus mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU