Ciconia ciconia [sik' uh nE uh sik' uh nE uh]

Description

The white stork stands up to 4 feet tall, has a wingspan of almost 7 feet, and weighs up to 10 pounds. It has long, bare red legs, and a straight pointed red bill. The head, neck and body are white, while the black wing feathers are highlighted with a sheen of purple and green iridescence. Males and females are similarly colored, but males are slightly larger. Juveniles are duller in coloration, and their black primaries are tinged with brown.

Distribution and Habitat

This stork breeds in several discontinuous populations across much of Europe, the Middle East, west-central Asia, and the northern coast of Africa, and winters in tropical Africa. In both parts of its range it prefers lowland open habitats of wet pastures, flooded meadows, and shallow lakes and marshes with scattered trees for roosting and nesting.

Because storks are rather heavy birds, they prefer to soar on thermal currents rather than fly and are therefore reluctant to fly over large bodies of water. To get to their wintering grounds, western populations cross the Mediterranean at the Straits of Gibraltar, while eastern populations cross at the Bosporus and circle through the Middle East.

Diet

Storks are opportunistic feeders, and take a wide variety of prey -- insects, frogs, toads, tadpoles, fish, rodents, snakes, lizards, earthworms, mollusks, crustaceans, and even the occasional chick or egg of a ground-nesting bird. They search for prey by walking along with bill pointed toward the ground. Wintering birds will often congregate around edges of grass fires to capture small prey fleeing the flames. Winter flocks will also congregate in large numbers and utilize locally abundant food sources, such as locust or grasshopper swarms.

Reproduction

White storks form into monogamous pairs for the duration of the breeding season, but those pairings are not permanent from year to year. Some pairs will come together over successive years due to a preference for a particular nesting site, but they do not necessarily make it a point to "join up" each year.

Both sexes participate in construction of the nest, which is a huge, bulky structure made from branches and sticks lined with twigs, grasses, sod, rags, and/or paper. Nests are often used over successive years, with each breeding pair adding new elements, and some nests have been in continuous use for hundreds of years. Manmade structures such as rooftops, chimneys, bridges, and telephone poles are utilized for nesting sites, as are sturdy trees and cliff ledges.

Three to five chalky white eggs are laid, and are incubated by both parents for 33 to 34 days. Both parents also participate in the feeding and care of the chicks, which fledge at 8 to 9 weeks. Sexual maturity is reached by the fourth year, and white storks have been known to live and breed up to 30 years or more in the wild.

Conservation Status

White stork populations are decreasing in some areas due to loss of habitat, as well as to loss of food sources in wintering grounds. The species is protected throughout most of its range.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class Aves
order Ciconiiformes
family Ciconiidae
genus & species Ciconia ciconia

Questions or comments about this page?

SKC Films Library >> Science >> Zoology >> Birds >> Order Ciconiiformes

This page was last updated on January 28, 2017.