This suggests that the prey is killed by a combination of hitting and gashing.
I didn't know about the gashing. Perhaps the article was mistaken, and they
really meant that the hind toe had evolved to withstand this kind of treatment,
not the beak.
Peter Shute
> -----Original Message-----
> From:
> On Behalf Of
> Angus Innes
> Sent: Wednesday, 27 March 2013 7:52 AM
> To: Birding Aus
> Subject: [Birding-Aus] 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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