Subject: [Tweeters] Raptors carrying prey
Date: Dec 20 14:01:20 2012
From: Bud Anderson - falconresearch at gmail.com


Not to beat this subject to death but, to me, it is very difficult to make
definitive statements about this subject. There are about 300 species of
raptors worldwide and their abilities and life styles vary enormously. Add
into the equation all of the physics involved and it gets complex fast.

You'd have to define the situation first. Are we talking about a raptor
taking off from the ground with prey and, if so, what shape is that prey,
does it have wings, legs, etc? How much resistance does it present? Is the
prey taken off the surface of a body of water while the bird is in flight
(Bald Eagles) or from a standstill at the surface (Ospreys)? Most
importantly to me is whether the prey is carried over a cliff, especially
with wind. And, of course, just how strong is that wind?

All of this comes from watching a tiny little adult male Barbary Falcon
(350 grams) on Lanzarote in the Canary Islands catch and carry a Rock
Pigeon (265-380 grams) to its nest from out over a vast gulf of air with
heavy winds next to a 1,500 foot cliff. I would have bet $1,000 that bird
could never have done that, but it did.

--
Bud Anderson
Falcon Research Group
Box 248
Bow, WA 98232
(360) 757-1911
falconresearch at gmail.com
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