American Kestrel Species Notes, Development Photos and Case Histories

The American Kestrel is the smallest member of the Falcon family, which also includes the Peregrine Falcon, the world’s fastest bird. Kestrels are much smaller, being scarcely larger than a Bluejay.  They are also the most colorful of our native hawks, especially the males, which have rusty red backs and tails, combined with blue wings. Both sexes have a black cap and a noticeable vertical line under the eye. Kestrels prefer to hunt over open ground for grasshoppers, crickets, and other insects, as well as mice, voles, and other small rodents. They are one of

the few hawks that can hover, a skill that allows them to maintain a fixed position in the air while pinpointing the location of their prey in the tall grasses where they usually hunt. In the Birmingham area, Kestrels appear to have a strong preference for the old field habitat around power plants and other industrial sites.  Since they are cavity nesters, they readily find nest sites in drain pipes and other openings in the factory buildings. They also nest successfully in the heart of downtown Birmingham. One nest site was in a drain pipe in the façade of the building on 20th Street just one block from Linn Park, in the heart of the business district.

Incubation requires about 30 days.  Nestlings begin to open their eyes only a day or two after hatching.  The mother broods the nestlings for only 8 to 10 days, as Kestrels develop rapidly, and fledge only 28 days after hatching. At this stage they might better be called branchers, because their flight is clumsy, and they spend much of their time perched on a low perch or concealed on the ground, where they may move around freely on foot. They develop their flight and foraging skills quite rapidly, however, and remain dependent on their parents for food for only a few weeks after fledging.  Except in fairly rare cases where a cavity nest is destroyed, most juvenile Kestrels are found in this brancher stage of development, making the task of reuniting fairly simple and straightforward.

 

American Kestrel (Falco sparverius)

Development Photos

Young Nestlings

 

Older Nestling

 

Older Nestling

 

Brancher

 

Case Histories

Case #1

Case #2

Case #3

Case #4

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