The common kestrel, Falco tinnunculus, is a bird of prey from the kestrel group within the falcon family Falconidae. It is also known as the European kestrel, Eurasian kestrel, or Old World kestrel. In the United Kingdom, it is often simply referred to as the "kestrel." This raptor is small compared to other birds of prey but larger than most songbirds, with long wings and a distinctive long tail.
Males and females exhibit sexual dimorphism in their plumage. The male has a blue-grey cap and tail with a black tip bordered by a narrow white rim. Its back is chestnut with black spots, and the underside is buff with black streaks. The female is larger and lacks the blue-grey coloring, having a brown back with black bars and a similar underside to the male. Both sexes have a prominent black malar stripe, bright yellow cere, feet, and eye-ring, with dark toenails, bill, and iris.
The common kestrel favors open habitats such as fields, heaths, shrubland, and marshland. It does not require woodland but needs alternative perching and nesting sites like rocks or buildings. It thrives in treeless steppes and can adapt to human settlements and various landscapes, from wetlands to arid savannas.
This species has a vast range, being widespread in Europe, Asia, and Africa, and occasionally reaching the east coast of North America. It has colonized some oceanic islands, though vagrant individuals are generally rare.
The common kestrel is diurnal and can be sedentary or migratory, depending on the region. It is known for its characteristic hunting behavior, hovering 10-20 meters above the ground before diving steeply onto prey. It is also capable of seeing ultraviolet light, which aids in detecting the urine trails of small mammals.
Breeding occurs in spring or the start of the dry season, with the kestrel preferring cavity nests in cliffs, trees, or buildings. Clutches typically consist of 3-7 eggs, which are incubated by both parents. The young fledge after 4-5 weeks and stay with the family for a short period thereafter.
The lesser kestrel and American kestrel are similar but not closely related. The lesser kestrel lacks black on the upperside except for wing and tail tips, while the American kestrel has much grey in the wings of males.
The common kestrel's diet consists almost exclusively of mouse-sized mammals, such as voles, shrews, and true mice. It may also consume small birds, particularly during the summer when fledglings are abundant. Invertebrates and arthropods can be significant food sources seasonally.
The IUCN lists the common kestrel as Least Concern. Its population has fluctuated but remains generally stable, with an estimated 1-2 million pairs globally. Some subspecies, such as those in the Canary Islands, are rarer and number less than 1000 adult birds.