Crane
Adaptations: The Legs and Feet
-
Long, skinny
legs are useful for standing in water without getting body feathers
wet, and also for balancing a long skinny neck when a bird is in flight.
(There are exceptions: geese and swans have long necks and short legs,
and Black-necked Stilts have very long legs and medium necks.) When
baby cranes hatch, their legs are short. Babies hatch early enough in
the season that plants aren't very tall yet, but a baby crane's legs
must grow very fast to keep up with plant growth so they can see over
the grass and leaves to follow their parents!
- An ornithologist
looking at a crane's feet would know that even if this bird spends
a lot of time in water, it isn't a swimmer. Why? Because there are no
webs between the toes.
- The toes
offer other clues. Most water birds, including ducks, geese, and sandpipers,
have short or missing back toes unless they perch in trees. A back toe
could slow them down, getting stuck in the mud, but it's very useful
when a bird perches in trees. Herons have long back toes because they
nest in trees. Cranes nest on the ground, so their back toe can be very
tiny, as for most other water birds. The toes are long enough to balance
and support the crane's body on squishy mud.
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