The Kestrel is a small, chestnut brown bird of prey that is frequently seen hovering over grassland. The hooked bill is a bluish colour with yellow cere. The legs are yellow.
The male (or tercel) Kestrel has black-spotted chestnut brown upper-parts, and a blue-grey head and tail. The tail has a single black bar at the tip. Underneath, the breast and belly are buff coloured with black spots.
The female (or falcon) is darker than the male and the back, mantle and wings all have black barring. The tail has black barring along its length. The creamy under-parts are more heavily streaked in black than the male. Occasionally, the head and tail may be tinged with grey.
Kestrels are similar in size to the Sparrowhawk but have more pointed wings. They are not fast or powerful fliers, and their wing beat is rather "flappy", but they can hover effortlessly for long periods of time by rapidly beating its wings while facing into headwind and matching the air speed precisely.
Kestrels feed on small mammals, such as voles, shrews and mice, birds as large as Starlings, and invertebrates, such as beetles, grasshoppers and worms. In gardens, they will take meat scraps.
In addition to having exceptionally good eyesight, Kestrels can also see ultra-violet light. This is useful in locating voles because they leave a trail of urine wherever they go and the urine glows in ultra-violet light.
They nest in a hole in a tree or on a ledge on cliffs or buildings, and simply line the hole or ledge with sticks and straw.
The eggs are about 39 mm by 32 mm, smooth and non-glossy, white or yellowish-buff with red-brown markings. Incubation is by the female only. Both adults feed the young birds, though the newly-hatched are usually fed by the female with the male hunting and bringing the food to the nest.