American Kestrel Research
American Kestrel numbers have declined across North America due to loss of habitat, loss of nesting sites and predation by larger raptors such as Cooper's Hawks. Members of CARRI are creating an American Kestrel nest box trail. When finished, the trail will stretch from Estes Park, Colorado to the Wyoming border.
We are interested in locations on private land where nesting boxes for the smallest North American falcon can be placed and monitored. American Kestrels prefer open country with a few trees. All we need is a post or tree in open country where a nest box can be placed. The middle photo below is a photo of one of our nesting boxes.
In 2016, we had a bumper crop of nesting American Kestrels with all but one of our nest boxes active with nesting kestrels. One nest (the second photo below) had 10, yes 10 eggs in it. A normal clutch is only 5 eggs.
Below are some photos of American Kestrels, including nests, eggs, young and adults.
Volunteers of CARRI are interested in answering these questions about American Kestrels
American Kestrel's raise more young in nest boxes than in natural cavities.
American Kestrel's raise, on average 5 young no matter how large their nest box is.
We have found as many as 10 eggs in a kestrel box (Photo above).
The timing in egg laying and hatching of young at different elevations varies by a few weeks. They begin egg laying earlier at lower elevations than higher ones.
Pairs of American Kestrel will nest closer to one another if the prey is adequate.
American Kestrels feed upon different prey items in different locations.
The diet of American Kestrels changes from summer to winter. In the winter, they feed upon voles, mice and birds. In the summer, they often prey upon insects lizards and snakes.