The Common Kingfisher, Alcedo atthis, also known as Eurasian Kingfisher or River Kingfisher, is a small kingfisher with seven subspecies recognized within its wide distribution across Eurasia and North Africa. It is resident in much of its range, but migrates from areas where rivers freeze in winter.
This sparrow-sized bird has the typical short-tailed, large-headed kingfisher profile; it has blue upper parts, orange underparts and a long bill. It feeds mainly on fish, caught by diving, and has special visual adaptions to enable it to see prey under water. The glossy white eggs are laid in a nest at the end of a burrow in a riverbank.
Description:
This species has the typical short-tailed, dumpy-bodied large-headed and long-billed kingfisher 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. It is about 16 centimeters (6.3 in) long with a wingspan of 25 cm (9.8 in), and weighs 34–46 grams (1.2–1.6 oz).
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.
Common Kingfishers are important members of ecosystems and good indicators of freshwater community health. The highest densities of breeding birds are found in habitats with clear water, which permits optimal prey visibility, and trees or shrubs on the banks. These habitats have also the highest quality of water, so the presence of this bird confirms the standard of the water. Measures to improve water flow can disrupt this habitat, and in particular, the replacement of natural banks by artificial confinement greatly reduces the populations of fish, amphibians and aquatic reptiles, and waterside birds are lost