The data from 16 years of Garden Bird Survey in Canberra reveals some
interesting things. When all years' data (42265 records, each for 52 weeks,
for 1042 observer years) are combined, both the Kestrel and Black-shouldered
Kite show strong patterns of seasonal changes of abundance (or at least
numbers recorded). Interestingly, this was well known many years ago for the
Aust Hobby, (for which the annual pattern is extremely regular) but it has
not been shown for these other species before (from this data set). The
patterns of the three species are quite different. Details will come out in
due course.
On an ad hoc level, a trip I did from Canberra down to Eden on 27-11-1998
revealed large numbers of Kestrels ie one or two every few km but almost no
other raptors (well one Brown Falcon and two W-tE).
-----Original Message-----
From: Ken Maling <>
To: Birding-aus <>
Cc: Tony Russell <>
Date: Thursday, 17 December 1998 8:39
Subject: Re: BSK and Kestrel absences.
>Tony Russell wrote:-
>
>
>>Re recent discussion about the absence of Black-shouldered Kites, we in
>SA
>>have frequently commented on an apparent absence of these birds on SOME
>DAYS
>>in areas where they are normally quite abundant. A similar phenomenon has
>>been observed with Kestrels. Sometimes we go a whole day's driving
>without
>>seeing one. Other days they seem to be everywhere......./snip
>
>We have made similar observations in and around Somers, Vic.
>
>As a matter of interest we seem to have had an unusually high number of
>days with easterly winds this year and have recorded very few sightings of
>any raptors on days when wind was easterly. Maybe there is a connection?
>
>Regards
>
>Ken Maling
>
>Somers, Vic
>
>
>
>
>
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