BIRDS ’ TECHNIQUES
FOR GLIDING
It requires a great deal of energy to fly. However, birds are small creatures
and the energy they can store in their bodies is limited. Birds obtain most
of the energy they need by means of applying special flying techniques.
Gliding in the air without flapping their wings is one of the techniques that
they use most. For example, vultures employ a special method based on ris-
ing heat currents in order to glide at a convenient altitude. Gliding from
one current to another, they can cover a vast area in a day.
Migratory birds, too, make use of gliding techniques to save energy. Storks,
for example, use heat
currents to fly during mi-
gration. White storks of
central Europe migrate to
spend winter in Africa
and cover a distance of
about 7,000 kilometers
(4,350 miles). If they
were to flap their wings
all the way to their desti-
nation, they would have
to take four breaks dur-
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W O N D E R F U L C R E A T U R E S
