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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