Fw: [Birding-Aus] raptor prey (was sea eagle observation) now Peregrine

Subject: Fw: [Birding-Aus] raptor prey (was sea eagle observation) now Peregrine stategy
From: "Mike Carter" <>
Date: Sat, 14 Jun 2008 10:45:25 +1000
On Thu, Jun 12, 2008 at 7:25 PM, Evan Beaver <> wrote:

Excellent response Phillip, exactly what I was thinking.

I can't imagine the impact that would be required on a bird in the
air, so with nothing to provide an opposing force, to dislodge the

Evan, it is obvious that you have not seen a stooping Peregrine hit another
bird, especially a big one, otherwise you would know considerable force is
Even more spectacular is the stoop of a Grey Falcon as they seem to do it
from even greater heights. I saw one stoop from several hundred metres.
Moreover, Evan, you don't have to imagine it. I'm not suggesting that you
can do this but the force could be estimated by calculation using a 500g
mass stooping at between 160 to 440 km per hour. You will of course have to
assume a stopping distance. Nevertheless, it will be substantial.
And of course there is an opposing 'force' - it's called INERTIA.
Other than being ripped off, that is one way the head might be dislodged.
The sudden acceleration of the body - the whiplash effect.
Perhaps you hadn't realised that the head rest on your car seat is to stop
your head moving BACK when your body moves FORWARD having been hit from
Nevertheless, it is probably rare for the head to be removed in flight.

Mike Carter
30 Canadian Bay Road
Mount Eliza  VIC 3930
Tel  (03) 9787 7136


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