Page 28 - The Miracle of Migration in Animals
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THE MIRACLE OF MIGRATION IN ANIMALS
Turtles
Experiments have also proved that migrating loggerhead turtles
(Caretta caretta) make use of the world’s magnetic field. These crea-
tures act as though they have prior knowledge of the intensity of the
magnetic field in different parts of the world, and when they set off in
the ocean they determine their direction of travel accordingly.
Kenneth J. Lohmann and his team from the University of North
Carolina have studied the migratory movements of these turtles. As
soon as they hatch on the eastern coast of Florida, these reptiles head
for the ocean and swim straight to a large current known as the
North Atlantic gyre that circles the Sargasso Sea. Turtles head to
the northeast of this gyre, which tends towards Europe and then
south. After spending from five to ten years in the warm and
rich waters of the gyre, they return to North America
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