Hi Laurie,
It depends how you define your survey. The short answer is obviously you
need to define your methods and keep to them, not decide which species are
and are not before the event, otherwise the survey is meaningless. Thus it
is I think irrelevant to ask if Tawny Frogmouths are garden birds, but that
about Boobooks and Powerful Owls may not be, even though they are much less
common and in marginal habitat. It depends on what fits the rules of the
survey. As for migrants, of course they should be included. Certainly in
Canberra, broadly speaking about a third of species are more common in
summer, about a third of species are more common in winter and the rest not
so obviously consistently different.
My book: as in The third edition of my report, entitled: "Canberra Birds: A
Report on the first 21 years of the Garden Bird Survey" goes into great
detail about this particular survey and the methods used for it. It is 130
pages. The report is based on the first 21 years of continuous data, from
53244 observer weeks of data, from 1316 observer years of data, from a total
of 294 sites. It also has a detailed discussion of the literature of urban
bird surveys around the world (three pages). It is a very useful reference
for anyone who has ever participated in or planned a long-term volunteer
based bird population survey.
Philip Veerman
24 Castley Circuit
Kambah ACT 2902
02 - 62314041
-----Original Message-----
From:
On Behalf Of Laurie Knight
Sent: Tuesday, 8 May 2012 9:15 PM
To: Birding Aus
Subject: What makes a species a "garden bird"?
Today's weather was lovely and fine - 100% azure sky, slight breeze,
temp in the mid 20s - just what you expect in Brisbane in May. You
have to go out at lunch time when conditions are like this.
As I was perambulating around the Roma St Parklands taking in the
floral displays set up for Mother's Day, I observed a Buff-banded Rail
fossicking through the garden beds. This led me to reflect on how
much time / proportion of lifecycle must a species spend in gardens to
qualify as a "garden bird"? (This begs the question as to what is a
"garden bird"?)
Clearly, species that breed in and spend extensive proportions of
their lives in urban parks and gardens qualify as garden birds. By
this measure, Bush Thickknees and Turkeys are garden birds. So are
Pacific Black and Maned Ducks, Eurasian Coots, Dusky Moorhens and Aus
Grebes.
Tawny Frogmouths would be garden birds, but what about Boobooks and
Powerful Owls? Do species that periodically visit gardens (like
Cassowaries) qualify? What about migrants (such as Koels) that
frequent gardens when they are in town?
Regards, Laurie.
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