Peregrines: from beaks to toes

To: "'Birding Aus'" <>
Subject: Peregrines: from beaks to toes
From: "Philip Veerman" <>
Date: Wed, 27 Mar 2013 13:33:15 +1100
Thanks for that. I will take on trust the comments from Stephen Ambrose,
which makes it a far more credible story. On the quote below, this clenched
foot idea, as in this quote has always seemed very strange to me: "The toes
are clenched, with the long hind toe projecting below the three front ones,
which are bent up out of the way." Apart from that "bent up" is completely
nonsensical. As a hypothesis is seems to have little if any evidence or

With feet adapted for grappling why would they close them? If "small, light
birds are seized in his outstretched foot", why then would the toes be
clenched for a big bird and what about in-between prey and at what point of
the attack does the falcon decide how to hold its toes? 

I read somewhere that another person has disputed this clenched foot idea on
the basis that the few photos available that show this attack appear show a
fully open foot.

I have long suspected that this clenched foot idea started during falconry
times of centuries ago, as a pure fantasy, based on that a human punch is
considered as more severe than a human slap (as if that was relevant).
Admittedly it is hard to get to see this from the ground but the few photos
that appear to show this (that were presumably not available for "J.A.
Baker's classic (1967) monograph on The Peregrine"), show the feet fully

Philip Veerman

To be fair to the research team, there is no reference in the original
scientific paper to Peregrines striking their prey in the air with their
beaks.  The paper can be downloaded online and the details are provided
below.  The paper was examining evolutionary divergence of the Peregrine and
Saker Falcons and investigated genes involved in beak development, olfaction
and arid environment-related homeostasis (osmoregulation and
thermoreguation).  So it's possible that reference to Peregrines using their
beak to strike prey was artistic licence by the BBC journalist reporting the

Stephen Ambrose
Ryde NSW 

-----Original Message-----
 On Behalf Of Angus Innes
Sent: Wednesday, 27 March 2013 7:52 AM
To: Birding Aus
Subject: Peregrines

I had exactly the same reaction as Peter Shute to the BBC report of the
Cardiff Universty study on Peregrine and Saker beaks. The beaks are not
designed for impact as suggested, the feet are - and in the case of the
Peregrine with a built in killing spike. I reached for J.A. Baker's classic
(1967) monograph on "The Peregrine" - the result of a 10 year study of the
bird in and over the woods, marshes and coast of East Anglia in the UK. 
I quote from page 26:"Killing is simple once the peregrine has the advantage
of his prey. Small, light birds are seized in his outstretched foot; larger
heavier birds are stooped at from above, at any angle from ten to ninety
degrees, and are often struck to the ground." The strike is described later:
"The peregrine swoops down towards his prey. As he descends, his legs are
extended forward till the feet are underneath the breast. The toes are
clenched, with the long hind toe projecting below the three front ones,
which are bent up out of the way. He passes close to the bird, almost
touching it with his body, and still moving very fast. his extended hind toe
(or toes- sometimes one, sometimes both) gashes into the back or breast of
the bird, like a knife. At the moment of impact the hawk raises his wings
above his back. If the prey is clean hit- it is usually hit hard or missed
altogether-it dies at once, either from shock or from the perforation of
some vital organ. A peregrin  e weights between 1 1/2 and 2 1/2 lbs: such a
weight, falling from a hundred feet will kill all but the largest birds.
Shelduck, pheasants, or great black-backed gulls, usually succumb to a stoop
of five hundred feet or more." (Baker goes on to describe the use of the
beak for tearing open the choice parts of the prey and for eating.) Baker
conducted all his ornithology in the field, not the laboratory. It is
usually the best starting point. Angus Innes.


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