Page 50 - The Miracle of Migration in Animals
P. 50
THE MIRACLE OF MIGRATION IN ANIMALS
Ducks
Pelican
Along with their fat deposits, birds probably
lose body water while flying non-stop. Accordingly, on night migra-
tions they can take advantage of the cooler air to lower their body
temperature and reduce water loss to a minimum, which affords
them increased flying distance.
Besides the species created with a suitable body structure for
night migration, there are also birds suited to daytime migration,
such as ducks, cranes, seagulls, pelicans, hawks and swallows. Storks
and condors that glide can fly by day only, because they depend on
rising heat currents or winds up the slope of mountains or hills to
help them stay aloft.
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