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.


6 comments:

  1. To show how adaptable those little falcons are: while they like your city scape, in Arizona they also annually nest in a cavity in one of our Saguaro Cacti that a Gila Woodpecker excavated. Ravens are their biggest problem, and the male fiercely, but not always successfully, tries to drive them off. When they are not breeding, the two kestrels like to sleep under the awnings of our patio. White lines of raptor uric acid mark their spots.

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  2. I am so jealous that you got to see one! I used to see them outside my apartment in Chicago, and the first time I saw one I instantly fell in love. I think they are so beautiful, and I have yet to see one in NYC. Might be time to take a walk down to BBP soon!
    Thanks for the post and I really enjoy your blog. Once I made a habit to tune into what was going on around me in the city, I have discovered so many neat things that you think one can only find outside of urban areas.
    -Ania
    http://aniagrzesik.blogspot.com/

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  3. Margarethe -- I can just picture them in a cactus. They are lovely anywhere and one of my very favorite birds to see. I have deep envy for a pair of kestrels sleeping on your patio!

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  4. Ania -- BBP seems like a good spot for a kestrel to take up residence, so maybe we will get lucky and it will stay.

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  5. I feed birds from my fire escape on the North Side of Williamsburg. We get a lot of finches, sparrows, starlings and mourning doves. The other day there was a huge commotion on the fire escape, causing all the birds to scatter. We looked outside and saw a female Kestrel! We believe she might have caught one of the starlings as our fire escape was strangely empty for days following.

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    1. Wow. That's exciting! I once saw a female kestrel grab a house sparrow out of the air above Central Park West, then sit on the NY Historical Society and eat it. Amazing how much wildlife interaction happens in the city.

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