The Common kingfisher (Alcedo atthis) is a small kingfisher widely distributed across Eurasia and North Africa. It is amongst the most colorful birds but despite its extraordinary colors, sometimes the Common kingfisher is difficult to see when it is in a dappled shade, and its colors are also not very obvious in flight. Furthermore, due to its shy nature, the Common kingfisher often remains hidden from a human's eye.
The Common kingfisher has the typical short-tailed, dumpy-bodied, large-headed, and long-billed shape. The adult male of the western European subspecies, A. a. ispida has green-blue upperparts with pale azure-blue back and rump, a rufous patch by the bill base, and a rufous ear patch. It has a green-blue neck stripe, white neck blaze and throat, rufous underparts, and a black bill with some red at the base. The legs and feet are bright red. The female is identical in appearance to the male except that her lower mandible is orange-red with a black tip. The juvenile is similar to the adult but with duller and greener upperparts and paler underparts. Its bill is black, and the legs are also initially black. Feathers are moulted gradually between July and November with the main flight feathers taking 90-100 days to moult and regrow. Some that moult late may suspend their moult during cold winter weather.
The Common kingfisher occurs throughout Europe and in Asia as far to the east as Japan, and south of the Sahara in Africa. Common kingfishers live year-round in the south, while northern populations fly south in winter away from the freezing water. In temperate regions, these birds inhabit clear, slow-flowing streams and rivers, and lakes with well-vegetated banks. They frequent scrubs and bushes with overhanging branches close to shallow open water in which they hunt. In winter Common kingfishers are more coastal, often feeding in estuaries or harbors and along rocky seashores. Tropical populations are found near slow-flowing rivers, in mangrove creeks, and swamps.
As with all kingfishers, the Common kingfisher is very territorial, mainly because each day it has to eat about 60% of its body weight. They even defend their territory against their mates and offspring. Individuals are solitary for most of the year, roosting in heavy cover beside their favorite hunting spot. When another kingfisher comes into its territory, the birds will both sit on a perch at some distance from one another and perform territorial displays, usually the display of beaks and plumage. Fights occasionally occur, one bird grabbing the other one’s beak and trying to hold their opponent under the water. Their flight is very fast, causing their wings to seem like a blue haze.
These birds communicate vocally and are well known for a long, trilling call like a repetition of the sound “chee”. During mating, the male whistles loudly to a female and will chase her through and above the trees. When diving for prey, their eyes are covered by a membrane and they rely on touch alone to know when they should snap their jaws shut.
Common kingfishers are serially monogamous and seek a new mate every year. They nest on their own. The female is given food by the male before copulation, usually a fish. 2-3 clutches of eggs are laid yearly, in April, and another by July, with sometimes, a third in early October. Nests are on sandy banks along streams. Sometimes they use a hole in a wall or a rotten tree stump, or a termite mound, where they dig a tunnel and at the end create a nest chamber.
Both the male and the female work to excavate a 50 to 90-cm-long burrow, taking turns. 6 to 7 white eggs are laid and incubation lasts around 19 to 21 days, done by both parents. Usually, the female does the brooding at night and both parents do it during the day. Young are given food by both their parents and they fledge at about 23-24 days, sometimes more. Four days later they make their first dive. Very soon they become independent and leave the territory where they were born.
The Common kingfisher in most parts of its range is indeed common, but it is under threat from river pollution, disturbances, and human developments. It is also vulnerable to bouts of severe winter weather, as it is unable to feed when bodies of water freeze over.
According to IUCN’s Red List, the global population of the Common kingfisher is around 700,000-1,399,999 mature individuals. Estimates for national populations include: in China, about 10,000-100,000 breeding pairs and 50-10,000 individuals on migration; in Taiwan, 10,000-100,000 breeding pairs; in Korea, 100-10,000 breeding pairs, with 50-1,000 individuals on migration; in Japan, 10,000-100,000 breeding pairs with 50-1,000 individuals on migration, and in Russia, 100-100,000 breeding pairs with 50-10,000 individuals on migration. The European population is estimated at 97,500-167,000 pairs, which equates to 195,000-334,000 mature individuals. Overall, currently, Common kingfishers are classified as Least Concern (LC) on the IUCN Red List.
Common kingfishers serve as a good indicator of the health of an ecosystem. As they feed on small aquatic animals, toxins in the water affect them severely. A strong kingfisher population therefore usually means a healthy habitat. Common kingfishers are also important predators throughout their range of small fish from freshwater habitats, thus controlling their populations.
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