Re: Red-rumped Parrot nesting site

David,

Of course it's due to a shortage of natural nesting hollows - for that
particular pair of birds in their particular situation. But it's not
necessarily an indication of some sort of "absolute" lack of nesting
hollows.

I expect that in some conditions artificial nesting sites will increase
populations above their "natural" level.

Railway structures are doing well as nesting sites for birds.
Kookaburras nested in a pylon in Cheltenham, near here, and Roger Hicks
wrote about Purple-crowned Lorikeets possibly nesting in stanchions in
Seaholme, west Melbourne, in the December 1997 ABW. 

Michael Norris
Hampton, Vic.