American Kestrel
The American Kestrel, formerly known as the Sparrow Hawk, is about the size of a Mourning Dove, making it the smallest falcon in North America. It typically perches on tall trees, or telephone lines and poles, surveying surrounding fields in hopes of finding insects or small mammals to eat. This female American Kestrel (her wings are rusty colored, males’ are slate-blue) flew down to the ground, captured an insect and returned to its telephone pole perch where it consumed its meal. If you look closely at the perched kestrel, you’ll see a notch in its upper bill. Many falcons have this notch which is thought to be an adaptation for severing the spinal column of vertebrate prey.


So interesting!
April 10, 2012 at 1:36 pm
Love Kestrels. Great post.
April 10, 2012 at 2:20 pm
love it!
April 10, 2012 at 5:34 pm
You can tell it’s a female even without seeing the wings. The female’s breast is streaked, the male’s dotted.
April 10, 2012 at 5:39 pm
The “notch” in the Kestrel’s upper bill is because of the bones it’s chewed through and worn the bill away? Or (as your description infers) it grows that way (“an adaptation”). Question: If the notch you refer to is an adaptation, then one should expect to see the same notch throughout the same species. Thanks.
April 16, 2012 at 2:56 pm
Hi Dan,
Most species of falcons are born with this notch in their upper bill…all American kestrels, for example, have this notch, as you surmised! Great question!
April 16, 2012 at 3:54 pm