WEEK FEET MY FOOT!
This comes from an European swift discussion site.

"The ?foot? of a Common Swift is no bigger than a pea when examined by
hand. Furthermore the Common Swift cannot walk the way birds usually
walk. It crawls or drags itself, on a flat surface because its legs,
feet, and toes are designed for clinging to a vertical surface rather
than walking. Because it cannot take big steps, when a Common Swift
walks it moves like a reptile, turning its body from one side to the
other.

However, the feet of some swifts, including those in Apus, are very
strong!?? These swifts use them for grasping/fighting, and some fights
last for hours. Furthermore, they use their feet for braking when they
land. Arkel (1997) has recorded that the Swift enters its nest box at
70 km/h. When the entrance hole is big enough, it will fly straight
through it and then must land on its feet at high speed. Its feet
therefore have a fraction of a second to bring to rest a mass of about
35-50 grams moving at 70 km/h. Even if the bird uses an upward curve to
reduce the force of the landing, its feet must still absorb a
considerable impact. When the shape of the nest site does not allow
these techniques the feet have to stand a seemingly impossible pressure
of about 40 kg, raising the question of exactly how the Swift achieves
this."


It's been suggested that the tail is also used in help bring the bird
to a stop.

Larry Schwitters
Issaquah










































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