Urban Wildlife Guide: American kestrel

Sunday, April 10, 2016

Kestrel Courtship

The American Kestrel is North America's smallest falcon. They are common in New York City. Despite being only about the size of a robin, they are deadly predators that swoop from the sky to seize insects, rodents, and small birds. It is not unusual to see a kestrel with a mouse dangling from its talons flying over a New York City street.

The other day I was walking in Brooklyn when I heard urgent sounding calls of klee klee klee from above. Two kestrels were flying over the buildings, a male and a female. Male kestrels have slate blue wings with rusty backs and tails. Females have reddish brown wings, backs, and tails, with no blue. Both sexes are pale below and have vertical black bars on the sides of their pale faces.

The birds I saw were making a commotion, darting and calling -- and the male was carrying something. The female landed on an antennae on the roof of a Brooklyn brownstone. The male landed nearby. He had a small bird in his talons! Captured prey! In what I think was an incidence of courtship feeding and with lots of wing flapping, the male passed the prey to the female and then took a seat again while the female tore into her nuptial meal. Sorry I could not get closer for details with the camera I had with me, but you'll get the idea from below. Click on the photos to enlarge.

Sunday, January 8, 2012

American Kestrel

The American kestrel, Falco sparverius.

I saw a bright male American kestrel land on a utility pole yesterday in Brooklyn Bridge Park. The American kestrel is the smallest falcon in North America. It is also the most numerous, most colorful, and most widespread. Although it is only the size of a robin, it is as deadly to its prey as any falcon– it swoops from the sky to catch and kill live insects, rodents, and small birds.

The kestrel in the photos is a male. He is between eight and ten inches long. Female kestrels are slightly larger. Both genders have two vertical black stripes on white faces, black talons, dark eyes, and reddish brown backs and upper tail surfaces. Males have bluish grey wings.

As I watched, the kestrel hunted using a sit-and-wait strategy: it perched high, bobbing and turning its head to scan the ground below for prey. Had it found something worthwhile, it would have swooped down to grab it with sharp talons. Kestrels are fast, graceful, and deadly. They sometimes also hunt by hovering stationary in the air, looking down. And they fly distinctively -- pointing their wings down and back with each stroke as if rowing, interspersed with periods of fast stiff-winged glides, until soundlessly falling upon prey.

It is not unusual to see a kestrel flying over a New York City street with a mouse dangling from its talons. Kestrels can find lots to eat here, and plenty of places to live. They are secondary cavity-nesters; they build nests in cavities, but they do not excavate them. They use holes made by woodpeckers, naturally occurring holes in trees and cliffs, and spaces in buildings and other man-made structures.

American kestrels are in New York year round. They breed across the United States, Canada, and Mexico. In winter, the northern-most breeders migrate south and some that breed further south migrate as far as Central America.

I have seen kestrels flying down Broadway in Manhattan, sitting on windowsills of fancy apartment buildings, and perching on traffic lights at busy intersections. When I drive on the New Jersey Turnpike I see them perched on utility poles scanning for prey in the short grass on the shoulders of the highway. The one in the photos is the first I have seen in Brooklyn's new park. I hope is stays.

The American kestrel is also called the sparrowhawk.