One
question that we are asked at every show or talk that we do is
"aren't you afraid that they'll bite you?".
Now,
it's true that a falcon can give you quite a nasty nip but what
we really worry about is the feet!
Toes
All raptors have four toes which, like the leg as far as the ankle
joint, are covered with scales on the upper side. The skin on the
underside is covered with small lumps, or spicules, which give good
grip on prey (the skin of the Osprey is particularly rough to enable
it to grip slippery fish better). The rear toe points backwards,
the middle one forwards and the other two roughly at 45º to
the front toe and with some flexibility for front and sideways movement.
Again, Ospreys differ slightly as they have the ability to move
their toes so that two face forward and two backward (an ability
shared by owls) to maintain good grip on a struggling fish.
Bird
catchers, such as falcons and some hawks, have an especially elongated
middle toe with more pronounced pads on the underside to enable
the foot to better wrap around and grip the body of the prey. Raptors
which predominantly hunt mammals, such as buzzards, eagles, harriers
and kestrels, have proportionately shorter toes. Whatever the length,
at the end of each toe are to be found the
Talons
Made of keratin (like our finger nails) these are the tools with
which the raptor seizes and kills its prey. Capable of striking
with lightning speed, the bird will generally aim to seize its prey
on or near the head and drive the needle-sharp talons into the quarry
until it is dead. The middle toe also has an edge to it which helps
to open up the skin of the prey. The talons have a central "quick"
of blood which enables continual growth, but the length of the talons
is kept down by everyday wear and tear.
Power
Awesome. Absolutely awesome. From the kestrel squeezing a field
vole to the European eagle owl crushing the skull of a young roe
deer or the Philippine Eagle catching monkeys, a raptor's feet contain
massive strength. The toes work on a sort of ratchet system, and
with each contraction the talons are driven in deeper and are not
released until the prey ceases to struggle. The advantage of the
ratchet system is that it enables the bird to exert a massive amount
of grip which, thanks to the ratchet, can be maintained even if
the muscles are relaxed. The disadvantage is that sometimes the
bird has difficulty unlocking the ratchet and it can be involuntarily
locked into the object of its attentions, not a happy state of affairs
if you're a buzzard locked into a rabbit when a fox hoves into view.
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