At 16:10 15/12/98 +1000, you wrote:
>Like Jill Denning, I must also throw a spanner into the works. I have in
front of me my notes for two hours (6am to 8am) on the 23 November 1991 for
my yard at Jandowae. Unlike Jill, I had not been there long enough to make
any changes and the yard consisted of a few gums and melaleucas with the
balance as lawn (using the word in its loosest context). This yard totalled
about 24 perches (I'm an old guy).
>
>The most common birds were Miners (Noisy and Yellow-throated), Magpies,
Galahs, Crows and Currawongs. The list for the two hours totalled 37 with 5
species of parrots, 5 species of Honeyeaters (plus the Miners), 2
Cuckoo-shrikes, etc.
>
>As well there were Double-barred Finches and Yellow-rumped Thornbills
nesting in the Melaleucas and Superb Fairy-wren running all over the lawn.
>
>There were also Sparrows and Common Starlings. Sorry John Holt, bang goes
another theory.
>
>Terry Pacey
>Toowoomba.
>
" a single garden does not a theory make"
The reports by Jill Denning and Terry above are most interesting but don't
necessarily
knock out my theory. It may be that the more rural gardens have different
dynamics to the
suburban ones.
The results I mentioned earlier come from a QOS garden bird survey with a
sample of 51 gardens
in suburban Brisbane, each with a minimum of 8 weeks of observation (many
with much more).
These results clearly indicated that gardens with a high frequency of NM had
low frequencies of
Sparrows (and to a lesseer extent other small native birds).
Our own garden in Moorooka is a sad testimony to this. Initially it was full
of lantana, no NM
and many small native birds. I cleared out the lantana (replanted with
native plants - they are
growing slowly) but alas the NM moved in and most small birds disappeared.
I think that this is cause and effect - but there could be other factors too.
These interactions are fascinating. I'll be starting up another QOS garden
bird survey in 1999,
20 years on from my first, and I hope to get lots of observers so that we
can look at some of
these issues further.
Cheers
Peter
Dr Peter Woodall email =
Division of Vet Pathology & Anatomy
School of Veterinary Science & An. Prod. Phone = +61 7 3365 2300
The University of Queensland Fax = +61 7 3365 1355
Brisbane, Qld, Australia 4072 WWW = http://www.uq.edu.au/~anpwooda
"hamba phezulu" (= "go higher" in isiZulu)
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