How fast is fast? Are we talking about speed in a short burst, or
sustained flight over distance?
We can assess the long-distance speed of those waders which have
have geo-locators attached to them.
If we could attach such a thing to Swift Parrots, we could trace
departure and arrival on migration (assuming the locators could be
recovered).
I don't know if Swifties have even been banded, though they should be.
When we trace a bird's speed by following with a car, this is seldom
over more than a kilometre, often very much less. Most birds are
capable of bursts of high speed when escaping - or when hunting, in the
case of raptors. Long distance travel is another matter, whether on
migration or commuting between roosts and food, as Galahs and Ibis do.
On migration, I would back Swift Parrots, and as commuters, Galahs.
Their flight looks easy, rather gull-like, without wild flapping, but
they can keep it up for a long way.
Anthea Fleming
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