Ciconia ciconia

Geographic Range

European white storks breed throughout Europe, North Africa, Asia Minor, and the Middle East, although they have a fairly fragmented distribution within that large area. Breeding populations have been extirpated from many areas of Europe historically. They migrate into tropical Africa, parts of the Middle East, and the Indian subcontinent during the winter.

• Biogeographic Regions
• palearctic palearctic
  • native native
• oriental oriental
  • native native
• ethiopian ethiopian
  • native native

Habitat

White storks inhabit open wetlands, savannas, steppes, meadows, pastures, and agricultural fields throughout their range. They prefer areas with shallow, standing water that are not too cold or humid. Their habitat preferences coincide with human preferences for agricultural areas and settlements, resulting in a long-term commensalism. During the breeding season, white storks also seek out areas with suitable structures on which to build nests, especially sunny sites on tall trees or rooftops. They have also been known to nest on walls, stacks of hay and straw, ruins, chimneys, and artificial nesting platforms.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland

• Wetlands
• marsh marsh

• Other Habitat Features
• urban urban
• suburban suburban
• agricultural agricultural
• riparian riparian

Physical Description

White storks are large, wading birds. They are covered in white feathers, except for the black primary feathers on their wings. They have long, sharp bills, and slender legs that are bright orange. Hatchlings and young have black bills and yellowish gray legs. Adults stand from 100 to 115 cm stall, with half of that height being made up by the legs. Their wingspan is 155 to 165 cm. Males are larger, on average, than females but both sexes are identical in plumage.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike
• male larger

Reproduction

White storks begin their mating season each spring when males return to breeding grounds, in March or April. Males arrive a few days before females. While waiting for females, males enlarge the nest which he and his mate used the previous year. The male and female make soft cooing noises to each other as a form of courtship, and make loud, noisy warnings to keep intruders away.

Initially, when a female rejoins a male, he carries out the "head-shaking crouch" display. In this display, the male lowers himself into the nest as in an incubating posture. Then, he stretches out his long neck and begins to shake his head from side to side. Next, the male and female will cement their pair bond with an "up-down" display, in which the birds pump their heads up and down with outstretched wings. This display is also accompanied by clattering of the bills.

Ciconia ciconia remain in life-long monogamous mating pairs from the age of three or four. Because of this, there is a close pair-bond between the male and female.

• Mating System
• monogamous monogamous

White storks nest in loose, informal colonies and breed in small groups, consisting of only a few pairs. These pairs may nest within sight of each other, but not terribly closely. Nests are huge and bulky and are constructed from sticks, branches, rags, paper, and other available materials. Nests can be up to 2 meters in diameter and 3 meters in depth. Ciconia ciconia make one of the largest nests of all birds. Both males and females participate in nest building, but males tend to bring more of the materials. Nests have been built on towers, rooftops, walls, haystacks, telephone poles, chimneys, constructed nest towers, trees, cliff-ledges, and occasionally on the ground.

White storks mate yearly. Females lay between 3 and 6 eggs, which hatch after roughly one month. Young white storks may leave their nesting grounds and be independent after about eight weeks. They do not begin reproducing until they are about four years of age.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Nest-building is an important part of parental care because it creates a suitable environment for the young. Both males and females spend time incubating the eggs, feeding hatchlings, and protecting fledglings. Regurgitated food is fed to the young by both parents each hour until the hatchlings reach 10 days old, then every two hours until they reach 15 days old. Young begin to fledge between 58 and 64 days old and become independent 7 to 20 days later.

• Parental Investment
• precocial precocial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifespan/Longevity

The oldest recorded lifespan in the wild is 25 years, captive individuals may live up to 48 years. Mortality after the second year of life has been estimated at 21%, before 2 years of age it may be 30% or higher.

Behavior

White storks generally occur in loose groups. During the breeding season white storks nest in small groups, but their nests are not close enough to be able to hear or see other pairs. Non-breeding individuals may occur in groups of up to 40 or 50 during breeding season. They form large groups of hundreds or thousands during migration and in their winter range. Their large size and carnivorous habits means that they must fly to foraging areas and that they need to take advantage of soaring and gliding whenever possible. They can sometimes be seen riding thermals and take advantage of patterns of rising air along migration routes. They are active during the day and not territorial.

• Key Behaviors
• terricolous
• flies
• diurnal diurnal
• motile motile
• migratory migratory
• social social

Communication and Perception

White storks communicate through vocalizations and through postures and movements. Tactile communication occurs between the parents and the infant as well as between the male and the female during mating behaviors. For example, after 14 days old, young white storks tap their parents bills to beg for food.

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

White storks eat a variety of prey that includes insects, scorpions and spiders, frogs, tadpoles, fish, toads, rodents, lizards, snakes, crustaceans, earthworms, small mammals, and hatchlings or eggs of ground-nesting birds. Foraging Ciconia ciconia visually search for food while walking with their bill pointed toward the gound. When they detect prey, white storks jab their bill forward to grab their prey. In dry years they eat mainly insects and mice. In wet years they eat mainly aquatic animals. Plague insects, such as locusts ( Schistocerca gregaria , Locustana pardalina , Dociostaurus maroccanus ), armyworms ( Spodoptera ), and caterpillars ( Laphygma exempta , Chloridea obsoleta ), form an important part of the diet in areas or years when they become abundant. The primary prey taken varies greatly with regional abundance of prey.

• Primary Diet
• carnivore carnivore
  • eats terrestrial vertebrates
  • insectivore insectivore
  • eats non-insect arthropods
  • vermivore

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• fish
• eggs
• insects
• terrestrial non-insect arthropods
• mollusks
• terrestrial worms
• aquatic crustaceans

Predation

There are few predators of adult Ciconia ciconia . Nestlings and fledglings may be preyed on by hawks and eagles. White storks place their nests in high places, protecting their young and eggs from most terrestrial predators. They also vigorously defend the young.

Ecosystem Roles

White storks influence the populations of their prey items. They have a long-term association with humans in the Palearctic because they prefer similar areas to those preferred by humans for agriculture.

Economic Importance for Humans: Positive

The benefits of Ciconia ciconia come largely from their aesthetic value. They also help to control populations of agricultural pests, such as grasshoppers.

• Positive Impacts
• controls pest population

Economic Importance for Humans: Negative

White storks often build their large stick nests on rooftops, chimneys, and electrical towers, which can be both dangerous and an annoyance. In some areas the presence of stork nests is seen as a sign of good luck and nests are tolerated.

• Negative Impacts
• household pest

Conservation Status

The breeding population of Ciconia ciconia declined during most of the twentieth century. This population decline was largely due to the destruction of suitable feeding habitats because of intensified agricultural development. However, white stork populations have rebounded by 20% in recent years because of land use policies, particularly in Spain and eastern European countries. Conservation efforts include preserving wetlands through the EcoFund Foundation and the Polish Society of Wildlife Friends. Preserving wetlands is not the only conservation effort. White storks can also build their huge nests on rooftops. In areas where they are not tolerated or nests are deemed dangerous, the Polish Pro-Natura Society removes and relocates them. White stork populations in Poland are especially healthy, it is said that 1 in every 4 white storks is "Polish."

Other Comments

White storks are important cultural icons in Europe. The arrival of a white stork was once thought to herald the arrival of a new baby. They are also the official birds of Lithuania and part of the symbol for the city of The Hague, Netherlands.

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (author, editor), Animal Diversity Web.

References

Berthold, P., K. Michael, U. Querner. 2004. Long-term satellite tracking of white stork migration: constancy versus variability. J Ornithol , 145: 356-359.

Cramp, S., K. Simmons, I. Ferguson-Lees, R. Gillmor, P. Hollom, R. Hudson, E. Nicholson, M. Ogilvie, P. Olney, K. Voous, J. Wattel. 1977. Handbook of the Birds of Europe the Middle East and North Africa . Oxford: Oxford University Press.

Goutner, V., V. Liordos, E. Tsachalidis. 1993. Growth of White Stork Ciconia ciconia nestlings. Ardea , 1: 133-137.

Latus, C., K. Kujawa. 2005. The effect of land cover and fragmentation of agricultural landscape on the density of white stork in Brandenburg, Germany. Polish Journal of Ecology , 53: 535-543.

Tryjanowski, P., T. Sparks, Z. Jakubiec, L. Jerzak, J. Kosicki, S. Kuzniak, P. Profus, J. Ptaszyk, A. Wuczynski. 2005. The relationship between population means and variances of reproductive success differs between local populations of white stork. The Society of Population Ecology and Springer-Verlag , 47: 119-125.

Tryjanowski, P., T. Sparks, J. Ptaszyk, J. Kosicki. 2004. Do White Storks always profit from an early return to their breeding grounds?. Bird Study , 51: 222-227.

Wuczynski, A. 2005. The turnover of White Storks on nests during spring migration. ACTA Ornithologica , 40: 83-85.

BBC. 2003. "How do white storks adapt to their environment?" (On-line). Science and Nature: Animals. Accessed January 24, 2006 at http://www.bbc.co.uk/nature/animals/features/180index.shtml .

Living Lakes Partnership. 2005. "Living Lakes" (On-line). White Stork Conservation: For Nature and People. Accessed March 24, 2006 at http://www.livinglakes.org/milicz/storks.htm .

BirdGuides. 1999. "White Stork, Ciconia ciconia" (On-line). BirdGuides. Accessed March 20, 2006 at http://www.birdguides.com/html/vidlib/species/Ciconia_ciconia.htm .

Smithsonian National Zoological Park. 2001. "White Stork- fact sheet" (On-line). Poland.pl. Accessed January 24, 2006 at http://poland.pl/spec/storks/facts.htm .

Wikipedia. 2006. "White Stork" (On-line). Wikipedia. Accessed March 20, 2006 at http://en.wikipedia.org/wiki/White_Stork .