Kestrels are small, colorful raptors belonging to the genus Falco, which also includes the peregrine and gyrfalcon. They are among the smallest members of the falcon family and are found across nearly every continent, adapting to diverse environments worldwide. Kestrels are recognized for their distinctive hunting strategy involving stationary flight, a behavior that has earned some species the common name of “windhover.” Their ability to thrive near human development has made them one of the most widespread birds of prey. They are often seen perched on utility wires or fence posts, scanning the ground for their next meal.
Classification and Key Identifying Features
Kestrels are taxonomically placed within the family Falconidae, a group of birds characterized by pointed wings and rapid flight. Common species, such as the Common Kestrel (Falco tinnunculus) and the American Kestrel (Falco sparverius), are distinguished by their small size and slender build. American Kestrels are the smallest falcon in North America, typically weighing 80 to 165 grams. They possess long, pointed wings and a notably long tail, which aids in their specialized flight techniques.
A visual identifier for many kestrel species is the presence of a dark, vertical stripe on each side of the face, often described as a “mustache” or malar stripe. The plumage generally consists of warm rufous or reddish-brown colors, frequently speckled or barred with black. Kestrels exhibit sexual dimorphism, meaning males and females have different color patterns and sizes. For example, the male American Kestrel displays slate-blue wings, while the female has reddish-brown wings and noticeable dark barring. Females are typically larger than males, a common trait among falcons that allows the pair to hunt a wider range of prey.
Unique Hunting Behavior and Prey
The kestrel’s most recognized hunting method is “kiting” or hovering, which involves remaining stationary in the air while scanning the ground below. This technique is executed by beating the wings rapidly and using the tail as a rudder to counteract the wind, holding a fixed position above a target. This stationary flight, sometimes called “windhovering,” is an energy-intensive but highly effective strategy for locating small, camouflaged prey.
Once prey is detected, the kestrel folds its wings and dives swiftly, ambushing the animal on the ground. Their diet is quite broad, centering on small terrestrial vertebrates and invertebrates. Primary prey includes small rodents like voles and mice, as well as insects such as grasshoppers and beetles. In some regions, small reptiles, amphibians, and birds are also included. Kestrels possess exceptional vision; some species can see the ultraviolet light reflecting off the urine trails left by voles, guiding them to the rodent’s location.
Geographic Distribution and Preferred Habitats
Kestrels have a near-global distribution across the Americas, Europe, Asia, and Africa, though they are generally absent from dense forests and polar regions. The American Kestrel is widespread throughout the Western Hemisphere, while the Common Kestrel is abundant across the Old World, spanning from Great Britain to China and south into Africa.
These falcons are highly adaptable and thrive in open to semi-open habitats where they have clear views for hunting. They prefer environments such as grasslands, meadows, deserts, and agricultural fields. The habitat must include open spaces for foraging and available cavities for nesting, since kestrels do not build their own nests. They frequently utilize natural tree cavities, abandoned nests, cliff ledges, or man-made structures like utility poles and buildings. This tolerance for human-modified landscapes means kestrels are often spotted in suburban and urban areas, perching on telephone wires or highway signs.