The Kingfisher, scientifically named Alcedo atthis, is a small bird built around life beside water. Its average body length is about 17 cm, its average wingspan is 26 cm, and its body mass averages 34 g.
It looks larger than it really is because of its long bill and compact body.
A Bird Painted by Light
The back, head, and wings show an intense blue-green sheen, while the breast and belly are chestnut. The blue appearance does not come from blue pigment in the feathers. Tiny structures inside the feathers scatter light and create the blue color seen by the human eye.
Watch one for two minutes beside a quiet river and it seems almost motionless until it suddenly disappears below the surface.
The Common Kingfisher has a mass range of 26 to 39 g and a wingspan of about 24 to 26 cm, giving it a compact shape suited to short, fast flights close to the water.
The bill also gives away its sex. A male has an all-black bill, while the lower part of the female's bill is chestnut.
From European Rivers to Japan
Alcedo atthis occupies a huge range across Europe and Asia, extending eastward to Japan, with populations in North Africa, the Nile Valley, and the Arabian Peninsula. It lives beside rivers, streams, ponds, lakes, wetlands, and coastal or brackish water.
It occurs from lowland rivers to mountain streams far inland, and northern birds face a serious problem in winter: frozen water hides their food. Populations in the north shift south when feeding areas close, while birds in warmer regions stay on the same stretch of water all year.
The Perch Above the Water
A kingfisher does not spend every hunting moment flying.
It sits on a branch, post, reed, or another perch above the water and watches for prey. When a fish enters the right position, the bird drops forward and dives.
Its eyesight is built for this job. The bird compensates for the change in light refraction between air and water, and a membrane covers the eyes during the dive.
Research has tested how water depth affects its fishing success. In a 2013 experiment, young Common Kingfishers were tested over water depths of 25 cm and 50 cm, with more attacks and greater success recorded in shallow water.
Count the seconds from the perch to the splash. The whole hunting movement is short enough to miss if you look away.
A Diet That Costs Energy
Small fish make up about 60% to 67% of the Common Kingfisher's diet. Aquatic crustaceans account for about 5% to 33%, while insects and other aquatic animals add further food sources.
The bird needs a large amount of food for its small body. Animal Diversity Web reports that it consumes around 60% of its body weight in food each day.
After catching a fish, the kingfisher returns to its perch and strikes the prey against it. The impact stuns or kills the fish and helps deal with species armed with sharp spines.
It swallows fish head-first.
After digestion, bones and other indigestible material are compressed into a pellet and later regurgitated.
The Tunnel in the Riverbank
Breeding pairs excavate a tunnel in a steep bank beside water. A normal tunnel is about 15 to 30 cm long, although a tunnel reaching 1.2 m has been recorded.
Both adults work on the nest and feed the young.
The nest chamber sits at the end of the tunnel, away from the entrance. The tunnel itself has been placed anywhere from 0.5 m to 37 m above the water level, depending on the site.
In one detailed breeding study, researchers measured a nest tunnel at 36.5 cm long, with an entrance measuring 8.25 cm vertically and 4.25 cm horizontally.
The female lays a clutch of 6 or 7 eggs in the common range described by Animal Diversity Web, while records extend to 10 eggs.
Twenty Days Inside the Dark
Incubation lasts about 18 to 21 days.
Both parents take part in incubation during daylight, while the female handles it at night according to the Animal Diversity Web account. The chicks hatch helpless and remain inside the tunnel before making their first trips outside.
Young birds leave the nest after about 23 to 27 days.
A breeding study from Bangladesh recorded an incubation range of 16 to 21 days, with an average of 18.5 days across 8 nests. The same study recorded clutches of 2 to 7 eggs, showing that clutch size shifts between nesting situations.
That variation matters when comparing studies from different regions.
A Dangerous First Year
The Common Kingfisher has an uneven life expectancy. Animal Diversity Web gives an average lifespan of 7 years, while AnAge lists a maximum wild longevity of 21 years.
British ringing data provide a much shorter figure: most birds that reach breeding age live about 2 more years.
The difference comes from the way these numbers are measured.
Young birds face heavy mortality during their first months, with Animal Diversity Web reporting that only about 50% of young survive to adulthood. In Britain, BTO data give first-year annual survival at 0.215 and adult annual survival at 0.28.
Cold Winters Leave a Mark
Winter weather hits populations hard because frozen water blocks access to fish. Animal Diversity Web records one striking example from Belgium: after a severe winter, a census found only 8 pairs. Five years later the count had reached 45 pairs before falling to 25 the following year.
That is a large swing for a bird living along narrow strips of suitable water.
Pollution matters too, because the species feeds directly on aquatic animals and sits high in freshwater food chains. Nestlings face additional danger from snakes and ground predators.
Adult kingfishers have few natural predators.
An Old Reputation by the Fishpond
Kingfishers were not always viewed kindly by people who managed fisheries. Animal Diversity Web records that anglers once regarded them as a threat to trout populations, yet only 7% to 28% of the fish they consumed were trout fry in the cited information.
In Britain, the bird carries an old piece of folklore: the saying "Only the righteous see the kingfisher" has been attached to sightings of this difficult-to-spot species.
There is another historical detail. During a 1954 debate in the British Parliament, Lord Grey of Fallodon was quoted discussing the kingfisher's unusually bright appearance in flight.
Even today, the bird spends most of its time hidden along the water's edge.
A Status That Hides Local Problems
The Common Kingfisher is classified as Least Concern on the global IUCN Red List, and BirdLife International's European Red List agrees.
That global category does not mean every local population is secure. Severe winters, declining water quality, reduced prey availability, and changes to riverbanks all hit local populations.
The species therefore gives scientists a useful view of freshwater habitat conditions, while the bird itself remains tied to accessible water holding enough prey.
In clear shallow water, the blue bird waits above the surface, and the next movement begins with a drop.
Source: Wikipedia — Common Kingfisher
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