Stork

Storks are large birds of the family Ciconiidae, comprising six genera and nineteen species, and found in much of the warm, dry regions of the world. Characteristics of these birds are the long neck, long legs and the large, often elongated beak. All storks are carnivorous, with the diet depending on the species. The best-known stork is perhaps the white stork (Ciconia ciconia), a bird as familiar in folklore as it is in European towns and villages.

Stork
Yellow-billed stork Mycteria ibis
Scientific classification
Kingdom Information
Domain	Eukaryota
Kingdom	Animalia
Subkingdom	Bilateria
Branch	Deuterostomia
Phylum Information
Phylum	Chordata
Sub-phylum	Vertebrata
Infraphylum	Gnathostomata
Class Information
Superclass	Tetrapoda
Class	Aves
Sub-class	Neornithes
Infra-class	Neoaves
Order Information
Order	Ciconiiformes
Family Information
Family	Ciconiidae
Population statistics

Description

In general, storks are characterized by a heavy build, long legs, long neck, and a long, stout bill. Broad-winged, storks use thermal air flows to soar and glide, conserving energy. Storks are gregarious year-round, and are usually found in large flocks.

Storks are medium to very large birds; outwardly they resemble the related herons, but in appearance seem more massive and heavy. Males are slightly larger than females. The smallest stork is Abdim's stork (Ciconia abdimii), standing at just over two feet tall and weighing 2.2 pounds. The largest is the marabou (Leptoptilos crumeniferus), which stands nearly five feet tall and weighs up to twenty pounds; with a wingspan in excess of ten feet, the marabou is among the largest living flying birds.

The beak is large, but very diverse in shape. The typical, slender bill is found only in the genus Ciconia; it is powerful with a slight upwards bend in the saddle-stork, giant stork and jabiru. It is especially large in the marabou, where it grows throughout its life and can reach over a foot in length; the marabou's stout beak is used to take food from deep within animal carcasses, where it competes with vultures. The yellow-billed stork and his relatives have a beak with a slight downwards bend containing sensory cells, which are helpful in finding food in the murky water.

The stork's foot has the first toe pointed to the back and the remaining three to the front (anisodactyl), with stunted webbing at the toe base. The long legs allow a slow walk. The wings are big and wide, well suited for gliding, interrupted by slow wing beats. Of the storks only the marabou flies with its neck retracted, the others fly with necks fully extended, enabling the laymen to distinguish them easily from herons. When storks fly in groups, they form no formations.

The plumage consists of black and white tones, which are distributed differently depending on the species. The black plumage often has a metallic sheen, which strengthens during the breeding season, in which white plumage also appears brighter. Many species have a completely unfeathered face, which in the marabou both head and neck are nearly naked.

Unlike many storks, storks are not voiceless. Croaking, squeaking and mooing sounds occur, with the addition of a beak rattle. The species of the genus Ciconia make whistling sounds, which are more pronounced with the black stork than with the white stork.

The name has its origins in either Old English (storc or stearc) or Old Norse (storkr), and refers to the stiff appearance of the birds when standing.

Species

• Genus Anastomus

African openbill, Anastomus lamelligerus

Asian openbill, Anastomus oscitans

• Genus Ciconia

Abdim's stork, Ciconia abdimii

Black stork, Ciconia nigra

Maguari stork, Ciconia maguari

Oriental white stork, Ciconia boyciana

Storm's stork, Ciconia stormi

White stork, Ciconia ciconia

Woolly-necked stork, Ciconia episcopus

• Genus Ephippiorhynchus

Black-necked stork, Ephippiorhynchus asiaticus

Saddle-billed stork, Ephippiorhynchus senegalensis

• Genus Jabiru

Jabiru, Jabiru mycteria

• Genus Leptoptilos

Greater adjutant, Leptoptilos dubius

Lesser adjutant, Leptoptilos javanicus

Marabou stork, Leptoptilos crumeniferus

• Genus Mycteria

Milky stork, Mycteria cinerea

Painted stork, Mycteria leucocephala

Wood stork, Mycteria americana

Yellow-billed stork, Mycteria ibis

Two species of bird have also been referred to as storks: the hammerkop (Scopus umbretta) and the shoebill (Balaeniceps rex). Both species have been classed with storks in the family Ciconiidae for a number of years; however, recent evidence indicates a relationship with pelicans.

Range and habitat

Storks are found on all continents except Antarctica. They are common in large parts of Eurasia, Africa, Australia and South America; in North America, on the other hand, they inhabit only the extreme south. Most species are native to the tropics; only three species live in the temperate zones.

In water and temporarily wet habitats storks are bound to very different degrees. Thus the yellow-bill and the open-bills life are found near the shore, while the marabou and Abdim's stork often stay far away from water in the open savannah. However, most species live at least near swamps, lakes or riverbanks.

Because the white stork migration is so famous, it may come as a surprise that most storks are not migratory birds. They stay close to their breeding grounds and move around relatively small-scale outside the breeding season. In contrast, the white stork belongs to the extreme migrators, with representatives of some northern European populations covering some 12,000 miles annually to reach the African winter quarters and return to their breeding grounds. The black stork and Oriental white stork breed in the temperate zone and migrate to tropical regions in winter. With the Abdim's stork, however, a tropical species is also a true migratory bird: it breeds in the steppes and semi-deserts north of the equator and overwinters in the eastern and southern African savannahs.

Nesting

For the most part storks are monogamous; they will mate for life, and return to the same nests every year. However, it has been observed that some storks have changed mates after migrations. Nests are large, up to six feet across and ten feet deep, with new material added every year. Eggs are laid in clutches of two to five, with an incubation period of between 25–35 days. Young reach maturity after four years, and as adults they have a life expectancy of between 30 and 40 years.