David Geering asked if Dubbo is the swift capital of Australia
right now given a series of records with up to 300 birds (at
least).
Perhaps he's right but in the late 1950s humble little Bayside
in SE Melbourne had counts on single days of at least 5000 in
1957 ("between 7.30 and 13.05 many thousands ...passed over in a
constant stream about 1/2 mile wide") and counts of around 1000
in the next 2 years (observations by Barbara Salter reported in
the Bird Observer).
It was a few years later that Ken Simpson organised people into
tracking these swifts and discovered that they roosted in tall
gums in the Great Dividing Range.
Over the last decade Fork-tailed Swifts have not appeared here
at all and White-throated Needletail numbers have been low.
So what's happened ? One guess is that our "pesticides" have
had a huge ecological effect (that would also explain how
difficult it is to see small bats around here). Another is that
- despite CAMBA etc. - circumstances between here and China (eg.
burning of forests = killing trees, understorey, insects...in
Indonesia) have decreased swift nos.
The ecological time-bomb is ticking and insect-eaters like these
swifts - the fastest birds in the world in level flight - are
victims ?
Michael Norris
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