Today, Brooklyn Bird Watch features a Heather Wolf photo of the male American Kestrel, North America’s smallest falcon, as photographed in Brooklyn Bridge Park.
This raptor, known as the “sparrow hawk,” is about the size of a Mourning Dove and is as colorful as it is fierce. The male’s slate-blue head and wings contrast elegantly with his rusty-red back and tail, and black raindrop-shaped spots on its white or light brown chest feathers. The female has the same warm reddish colorings on her wings, back, and tail, but does not have the prominent slate-blue color as the male.
The National Audubon Society tells us that the American Kestrel has diverse eating habits. Mostly, Kestrels eat large insects and small mammals, birds, and reptiles. Grasshoppers are among the favored prey; other favored large insects include beetles, dragonflies, moths, and caterpillars. American Kestrels also feed on mammals (including voles, mice, and sometimes bats), small birds (sometimes up to the size of quail), lizards, frogs, earthworms, spiders, and crayfish.
The Kestrel likes to hunt while perched on power lines or telephone poles, and will skillfully “hover” in mid-air against the wind by adjusting its long tail, surveying the landscape below and if it spots prey, it will attack from directly above the unsuspecting prey.
As the Cornell Lab of Ornithology points out, it’s tough being the smallest predator. The Kestrel is often the intended prey for Northern Goshawks, Red-tailed Hawks, Barn Owls, American Crows, and Cooper’s Hawks, as well as rat snakes, and even fire ants.
Wikipedia tells us that the American Kestrel is a common bird used in falconry, especially by beginners. Though not as strong a flyer as many other larger falcons, proper training and weight control by the falconer allows many American Kestrels to become effective hunters of birds in the size range of sparrows and starlings, with occasional success against birds up to approximately twice their own weight. The American Kestrel is leaner and less muscular than larger falcons. The pectoral flight muscles of the American Kestrel make up only about 12% of its body weight, as compared to about 20% for the strongest flying falcons such as the Peregrine.
The scientific name of the American Kestrel, Falco sparverius, is from the 18th century work Systema Naturae by the famous ornithologist Carl Linnaeus. It refers to the falcate (curved like a sickle), or hooked shape of the beak, while the specific name means “pertaining to a sparrow,” which is a reference to sparrows being a typical prey of the American Kestrel.
The American Kestrel is very adaptable. It has a wide range of eating habits, and can adapt to urban areas especially if there are nest boxes. The Cornell Lab of Ornithology notes that, “Kestrels are declining in parts of their range; you can help them by putting up nest boxes.”
I was curious about this small, beautifully marked predator with the large expressive eyes, so I went to YouTube and watched several video documentaries about the American Kestrel.
And sure enough, there was a video of a Japanese couple who set up one of those “nest boxes” for a pair of Kestrels on their small balcony. From the background, it looked like they lived about 20 stories up. A female Kestrel had started preparing a depression in the dirt that filled a large vase out on their balcony where she would soon lay 5 eggs.
When the couple, who lived in the apartment, made their presence known to the birds, the Kestrels looked up enigmatically at the camera with large dark eyes that seemed to be saying two things simultaneously: “I dare you to mess with the eggs,” and, “Please don’t harm the eggs.”
Once the chicks were born the couple would help the mother out by feeding the female kestrel pieces of chicken with a pair of chopsticks when it seemed like the male was taking a long time to return with a rodent or a lizard. The Kestrels seemed to catch on quickly that the humans were there to help.
At one point the couple gave her a whole chicken breast and let the mother feed the chicks as she wished. In time the mother Kestrel was willing to sit and watch while the Japanese couple fed the individual chicks pieces of chicken with the chopsticks (that was interesting to watch).
When the five chicks got to be too big for the vase, the couple made them a “room” out of a cardboard box (a “nest box”) while the mother Kestrel was out hunting.
Eventually, the chicks fledged, cautiously observing the world from the porch railing while exercising their wings. And, of course, in time all the chicks left the small porch balcony and the nest behind.
Not long after all the birds had left, while the couple were cleaning up the balcony porch, the female Kestrel returned, and just perched on the porch railing without moving, casually watching them clear everything away. The woman said she felt that the predator had returned to say thank you, and goodbye, and perhaps, only until next year.
This post first appeared on brooklyneagle.com
