Talons
vs. Beaks
Why
do you think eagles carry their prey with their talons instead
of their beaks?
Journey
North students came up with at least 14 different reasons! Here are
three answers from bird expert Laura Erickson, followed by the terrific
ideas students provided:
- Carrying
things in their mouths would make eagles' heads less streamlined,
so flight would be more difficult.
- Carrying
things in their mouths puts too much weight in front of their wings,
so flight would be much more difficult. It's easier for them to carry
things between their wings in the area that scientists call their "center
of gravity."
- Prey
animals might not move for a bit after attack, but they might still
be alive. If a prey animal suddenly revived and attacked, it would
be held far away from the eagle's face in the talons. (Even a tiny
mouse could bite an eagle's eye if it were held in its beak.)
Problems
With the Beak (Students' Answers):
- Another
eagle or strong bird could grab the fish out of an eagle's beak more
easily than out of his talons.
- Holding
prey in their beak would get in the way of an eagle seeing where
it is going.
- It leaves
their air passage clear so they can breathe with more efficiency.
- If eagles
carried their prey in their beak then the weight would be far forward,
throwing off their center of balance to make it harder to fly. By
carrying it in their talons they are pulling the weight rather than
pushing it through the air.
- If the
eagle had to make a call, it would open its beak and lose its food.
- The beak
might not be big or strong enough to hold big fish or ducks.
- If they
pant with the fish in their mouth, then the fish will fall out.
- Their
beaks are specially adapted to tear food, so the edge of the beak
is sharp and could slice or break things, and if the eagle bit down
on the fish with its beak, it would cut through the fish and the
pieces would drop while the eagle is flying.
Advantages
of the Talons (Students' Answers):
- The legs
and talons are designed for holding so they are much stronger than
the beak and make it easier to grab and grip the food
- They
don't catch the fish in their beaks because if they did catch it
with their beaks they would crash into the water or have a harder
time pulling up in the nick of time.
- Since
they catch their food with their talons, they don't want to switch
to the beak in midair because they might lose it.
- It is
easier for them to fly with greater speed with the food in their
feet.
- Their
4th rear toe, called the "hallux," helps to grip the prey.
- A slippery
prey would slip out of their curved beak. The talons have a better
grip on slippery fish.
- Two feet
are better than only one beak.
Also, an
eagle would have to carry a fish sideways in its beak, while it can
fly with the fish head-first in its feet by pulling one foot forward
of the other. This cuts down on the wind resistance as it flies.
Eagles don't have spicules (spiny scales) on their feet the
way osprey do, but those mighty feet are strong and the claws are sharp even
without the extra grip of those scales.
Read this
and other fascinating facts about eagle feet, toes, claws and talons:
National
Science Education Standards
- Each
plant or animal has different structures that serve different functions
in growth, survival, reproduction.
- Living
systems at all levels of organization demonstrate the complementary
nature of structure and function.
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