White Stork
Encyclopedia
The White Stork is a large bird
in the stork
family Ciconiidae. Its plumage
is mainly white, with black on its wings. Adults have long red legs and long pointed red beaks, and measure on average 100 – from beak tip to end of tail, with a 195 – wingspan. The two subspecies
, which differ slightly in size, breed in Europe (north to Estonia
), northwestern Africa, southwestern Asia (east to southern Kazakhstan
), and southern Africa. The White Stork is a long-distance migrant
, wintering in Africa from tropical Sub-Saharan Africa
to as far south as South Africa
, or on the Indian subcontinent
. When migrating between Europe and Africa, it avoids crossing the Mediterranean Sea
and detours via the Levant
in the east or the Strait of Gibraltar
in the west, because the air thermals on which it depends do not form over water.
A carnivore
, the White Stork eats a wide range of animal prey, including insects, fish, amphibians, reptiles, small mammals, and small birds. It takes most of its food from the ground, among low vegetation, and from shallow water. It is a monogamous breeder, but does not pair for life. Both members of the pair build a large stick nest, which may be used for several years. Each year the female can lay one clutch
of usually four eggs, which hatch asynchronously 33–34 days after being laid. Both parents take turns incubating the eggs and both feed the young. The young leave the nest 58–64 days after hatching, and continue to be fed by the parents for a further 7–20 days.
The White Stork has been rated as Least Concern
by the International Union for Conservation of Nature (IUCN). It benefited from human activities during the Middle Ages
as woodland was cleared, but changes in farming methods and industrialisation saw it decline and disappear from parts of Europe in the 19th and early 20th centuries. Conservation and reintroduction
programs across Europe have resulted in the White Stork resuming breeding in the Netherlands, Switzerland, and Sweden. It has few natural predators, but may harbour several types of parasite; the plumage is home to chewing lice
and feather mites, while the large nests maintain a diverse range of mesostigmatic
mites. This conspicuous bird has given rise to many legends across its range, of which the best-known is the story of babies being brought by storks.
by Linnaeus
in the landmark 1758 10th edition
of his Systema Naturae
, where it was given the binomial name of Ardea ciconia. It was reclassified to (and was designated the type species
of) the new genus
Ciconia
by French zoologist Mathurin Jacques Brisson
in 1760. Both the genus and specific epithet, cǐcōnia, are the Latin
word for "stork", originally recorded in the works of Horace
and Ovid
. The word stork is derived from the Old English word storc, and appeared in the tenth-century works the Erfurt Glossary, where the word is equated with Ciconia, and Aelfric's
Homilies. The word is related to the Old High German
storah, "stork", and similar words in many other European languages, all of which are descended from the Teutonic
sturko-z.
There are two subspecies
:
The stork family contains six genera in three broad groups: the open-billed and wood storks (Mycteria
and Anastomus), the giant storks (Ephippiorhynchus
, Jabiru
and Leptoptilos
), and the "typical" storks, Ciconia
. The typical storks include the White Stork and six other extant species, which are characterised by straight pointed beaks and mainly black and white plumage. Its closest relatives are the larger, black-billed Oriental White Stork (Ciconia boyciana) of East Asia
, which was formerly classified as a subspecies of the White Stork, and the Maguari Stork
(C. maguari) of South America. Close evolutionary relationships within Ciconia are suggested by behavioural similarities and, biochemically, through analysis of both mitochondrial cytochrome b
gene sequences and DNA-DNA hybridization.
has been recovered from Miocene
beds of Rusinga Island
, Lake Victoria, Kenya. The 24–6 million year old fossil could have originated from either a White Stork or a Black Stork
(C. nigra), which are species of about the same size with very similar bone structures. The Middle Miocene
beds of Maboko Island
have yielded further remains.
. The sexes are identical in appearance, except that males are larger than females on average. The plumage
is mainly white with black flight feather
s and wing coverts
; the black is caused by the pigment melanin
. The breast feathers are long and shaggy forming a ruff which is used in some courtship displays. The irises
are dull brown or grey, and the peri-orbital
skin is black. The adult has a bright red beak and red legs, the coloration of which is derived from carotenoid
s in the diet. In parts of Spain, studies have shown that the pigment is based on astaxanthin
obtained from an introduced species of crayfish (Procambarus clarkii
) and the bright red beak colours show up even in nestlings, in contrast to the duller beaks of young White Storks elsewhere.
As with other storks, the wings are long and broad enabling the bird to soar. In flapping flight
its wingbeats are slow and regular. It flies with its neck stretched forward and with its long legs extended well beyond the end of its short tail. It walks at a slow and steady pace with its neck upstretched. In contrast, it often hunches its head between its shoulders when resting. Moulting has not been extensively studied, but appears to take place throughout the year, with the primary flight feathers replaced over the breeding season.
Upon hatching, the young White Stork is partly covered with short, sparse, whitish down feather
s. This early down is replaced about a week later with a denser coat of woolly white down. By three weeks, the young bird acquires black scapulars and flight feather
s. On hatching the chick has pinkish legs, which turn to greyish-black as it ages. Its beak is black with a brownish tip. By the time it fledge
s, the juvenile bird's plumage is similar to that of the adult, though its black feathers are often tinged with brown, and its beak and legs are a duller brownish-red or orange. The beak is typically orange or red with a darker tip. The bills gain the adults' red colour the following summer, although the black tips persist in some individuals. Young storks adopt adult plumage by their second summer.
, Great White Pelican, and Egyptian Vulture
. The Yellow-billed Stork is identified by its black tail and a longer, slightly curved, yellow beak. The Great White Pelican has short legs which do not extend beyond its tail, and it flies with its neck retracted, keeping its head near to its stocky body, giving it a different flight profile. Pelicans also behave differently, soaring in orderly, synchronised flocks rather than in disorganised groups of individuals as the White Stork does. The Egyptian Vulture is much smaller, with a long wedge-shaped tail, shorter legs and a small yellow-tinged head on a short neck. The Common Crane
, which can also look black and white in strong light, shows longer legs and a longer neck in flight.
and North Africa in the west, and much of eastern and central Europe, with 25 percent of the world's population concentrated in Poland, as well as parts of western Asia. The asiatica population of about 1450 birds is restricted to a region in central Asia between the Aral Sea
and Xinjiang
in western China. The Xinjiang population is believed to have become extinct around 1980. Migration
routes extend the range of this species into many parts of Africa and India. Some populations adhere to the eastern migration route, which passes across Israel into eastern and central Africa.
A few records of breeding from South Africa have been known since 1933 at Calitzdorp, and about 10 birds have been known to breed since the 1990s around Bredasdorp
. A small population of White Storks winters in India and is thought to derive principally from the C. c. asiatica population as flocks of up to 200 birds have been observed on spring migration in the early 1900s through the Kurram Valley
. However, birds ringed
in Germany have been recovered in western (Bikaner) and southern (Tirunelveli
) India. An atypical specimen with red orbital skin, a feature of the Oriental White Stork, has been recorded and further study of the Indian population is required. North of the breeding range, it is a passage migrant or vagrant
in Finland, Great Britain, Iceland, Ireland, Norway, and Sweden, and west to the Azores
and Madeira
. In recent years, the range has expanded into western Russia.
The White Stork's preferred feeding grounds are grassy meadows, farmland and shallow wetlands. It avoids areas overgrown with tall grass and shrub. In the Chernobyl area of northern Ukraine, White Stork populations declined after the 1986 nuclear accident
there as farmland was succeeded
by tall grass shrub. In parts of Poland, poor natural foraging grounds have forced birds to seek food at rubbish dump
s since 1999. White Storks have also been reported foraging in rubbish dumps in the Middle East, North Africa, and South Africa.
The White Stork breeds in greater numbers in areas with open grasslands, particularly grassy areas which are wet or periodically flooded, and less in areas with taller vegetation cover such as forest and shrubland. They make use of grasslands, wetlands, and farmland on the wintering grounds in Africa. White Storks were probably aided by human activities during the Middle Ages
as woodland was cleared and new pastures and farmland were created, and they were found across much of Europe, breeding as far north as Sweden. The White Stork is a rare visitor to the British Isles
, though in 1416 a pair nested atop St Giles's Church in Edinburgh
, Scotland. A decline in population began in the 19th century due to industrialisation
and changes in agricultural methods. White Storks no longer nest in many countries, and the current strongholds of the western population are in Spain, Ukraine, and Poland. In the Iberian Peninsula, populations are concentrated in the southwest, and have also declined due to agricultural practices. A study published in 2005 found that the Podhale
region in the uplands of southern Poland had seen an influx of White Storks, which first bred there in 1931 and have nested at progressively higher altitudes since, reaching 890 m (3000 ft) in 1999. The authors proposed that this was related to climate warming
, and the influx of other animals and plants to higher altitudes. White Storks arriving in Poznań province in western Poland in spring to breed did so some 10 days earlier in the last twenty years of the 20th century than at the end of the 19th century.
ornithologist Johannes Thienemann
who commenced ringing studies in 1906 at the Rossitten Bird Observatory
, on the Curonian Spit
in what was then East Prussia
. Although not many storks passed through Rossitten itself, the observatory coordinated the large-scale ringing of the species throughout Germany and elsewhere in Europe. Between 1906 and the Second World War
about 100,000, mainly juvenile, White Storks were ringed, with over 2,000 long-distance recoveries of birds wearing Rossitten rings reported between 1908 and 1954.
from Kenya and Uganda south to the Cape Province
of South Africa. In these areas they congregate in large flocks which may exceed a thousand individuals. Some diverge westwards into western Sudan and Chad, and may reach Nigeria. In spring, the birds return north; they are recorded from Sudan and Egypt from February to April. They arrive back in Europe around late March and April, after an average journey of 49 days. By comparison, the autumn journey is completed in about 26 days. Tailwind
s and scarcity of food and water en route (birds fly faster over regions lacking resources) increase average speed.
To avoid a long sea crossing over the Mediterranean, birds from central Europe either follow an eastern migration route by crossing the Bosphorus to Turkey, traversing the Levant
, then bypassing the Sahara Desert by following the Nile
valley southwards, or follow a western route over the Strait of Gibraltar
. These migration corridors maximise help from the thermals and thus save energy. The eastern route is by far the more important with 530,000 White Storks using it annually, making the species the second commonest migrant there (after the Honey Buzzard
). The flocks of migrating raptor
s, White Storks and Great White Pelicans can stretch for 200 km (125 mi). The eastern route is twice as long as the western, but storks take the same time to reach the wintering grounds by either.
Juvenile White Storks set off on their first southward migration in an inherited direction but, if displaced from that bearing by weather conditions, they are unable to compensate, and may end up in a new wintering location. Adults can compensate for strong winds and adjust their direction to finish at their normal winter sites, because they are familiar with the location. For the same reason, all spring migrants, even those from displaced wintering locations, can find their way back to the traditional breeding sites. An experiment with young birds raised in captivity in Kaliningrad and released in the absence of wild storks to show them the way revealed that they appeared to have an instinct to fly south, although the scatter in direction was large.
s to soar and glide the long distances of their annual migrations between Europe and Sub-Saharan Africa
. For many, the shortest route would take them over the Mediterranean Sea
; however, since air thermals do not form over water, they generally detour over land to avoid the trans-Mediterranean flights that would require prolonged energetic wing flapping. It has been estimated that flapping flight metabolises 23 times more body fat than soaring flight per distance travelled. Thus, flocks spiral upwards on rising warm air until they emerge at the top, up to 1200–1500 m (4000–5000 ft) above the ground (though one record from Western Sudan observed an altitude of 3300 m (10,800 ft)).
Long flights over water may occasionally be undertaken. A young White Stork ringed
at the nest in Denmark subsequently appeared in England, where it spent some days before moving on. It was later seen flying over St Mary's, Isles of Scilly, and arrived in a poor condition in Madeira
three days later. That island is 500 km (320 mi) from Africa, and twice as far from the European mainland. Migration through the Middle East
may be hampered by the khamsin
, winds bringing gusty overcast days unsuitable for flying. In these situations, flocks of White Storks sit out the adverse weather on the ground, standing and facing into the wind.
is often encountered with White Stork flocks in southern Africa. Breeding pairs of White Stork may gather in small groups to hunt, and colony nesting has been recorded in some areas. However, groups among White Stork colonies vary widely in size and the social structure is loosely defined; young breeding storks are often restricted to peripheral nests, while older storks attain higher breeding success while occupying the better quality nests toward the centres of breeding colonies. Social structure and group cohesion is maintained by altruistic
behaviours such as allopreening
. White Storks exhibit this behaviour exclusively at the nest site. Standing birds preen the heads of sitting birds, sometimes these are parents grooming juveniles, and sometimes juveniles preen each other. Unlike most storks, it never adopts a spread-winged posture, though it is known to droop its wings (holding them away from its body with the primary feathers pointing downwards) when its plumage is wet.
A White Stork's droppings, containing faeces and urine, are sometimes directed onto its own legs, making them appear white. The resulting evaporation provides cooling and is termed urohidrosis
. Birds that have been ringed
can sometimes be affected by the accumulation of droppings around the ring leading to constriction and leg trauma. The White Stork has also been noted for tool use by squeezing moss in the beak to drip water into the mouths of their chicks.
, which acts as a resonator
. Used in a variety of social interactions, bill-clattering generally grows louder the longer it lasts, and takes on distinctive rhythms depending on the situation—for example, slower during copulation and briefer when given as an alarm call. The only vocal sound adult birds generate is a weak barely audible hiss; however, young birds can generate a harsh hiss, various cheeping sounds, and a cat-like mew they use to beg for food. Like the adults, young also clatter their beaks. The up-down display is used for a number of interactions with other members of the species. Here a stork quickly throws its head backwards so that its crown rests on its back before slowly bringing its head and neck forwards again, and this is repeated several times. The display is used as a greeting between birds, post coitus, and also as a threat display
. Breeding pairs are territorial
over the summer, and use this display, as well as crouching forward with the tails cocked and wings extended.
(Pelophylax kl. esculentus) and common frog
(Rana temporaria) and small mammals such as voles, moles, and shrews. Less commonly, they also eat bird eggs and young birds, fish, molluscs, crustaceans and scorpions. They hunt mainly during the day, swallowing small prey whole, but killing and breaking apart larger prey before swallowing. Birds returning to Latvia during spring have been shown to locate their prey, moor frogs (Rana arvalis), by homing in on the mating calls produced by aggregations of male frogs.
The diet of non-breeding birds is similar to that of breeding birds, but food items are more often taken from dry areas. White Storks wintering in western India have been observed to follow blackbuck
to capture insects disturbed by them. Wintering White Storks in India sometimes forage along with the Woolly-necked Stork
(Ciconia episcopus). Food piracy has been recorded in India with a rodent captured by a Western Marsh Harrier
appropriated by a White Stork, while Montagu's Harrier
is known to harass White Storks foraging for voles in some parts of Poland.
in trees, on buildings, or on purpose-built man-made platforms. Each nest is 1 – in depth, 0.8 – in diameter, and 60 – in weight. Nests are built in loose colonies. Not persecuted as it is viewed as a good omen, it often nests close to human habitation; in southern Europe, nests can be seen on churches and other buildings. The nest is typically used year after year especially by older males. The males arrive earlier in the season and choose the nests. Larger nests are associated with greater numbers of young successfully fledged, and appear to be sought after. Nest change is often related to a change in the pairing and failure to raise young the previous year, and younger birds are more likely to change nesting sites. A succession of pairs have been observed occupying a nest for a few days before moving on, the reason for which is unclear.
Several bird species often nest within the large nests of the White Stork. Regular occupants are House Sparrow
s, Tree Sparrow
s, and Common Starlings; less common residents include Eurasian Kestrels, Little Owl
s, European Roller
s, White Wagtail
s, Black Redstart
s, Eurasian Jackdaws, and Spanish Sparrow
s. Paired birds greet by engaging in up-down and head-shaking crouch displays, and clattering the beak while throwing back the head. Pairs copulate frequently throughout the month before eggs are laid. High-frequency pair copulation is usually associated with sperm competition
and high frequency of extra-pair copulation; however, extra-pair copulation is infrequent in White Storks.
A White Stork pair raises a single brood a year. The female typically lays four eggs
, though clutches
of 1–7 have been recorded. The eggs are white, but often look dirty or yellowish due to a glutinous covering. They measure 72.58 by 51.86 mm (2.9 by 2 in), and weigh 96 –, of which 10.76 g (0.379547832251005 oz) is shell. Incubation begins as soon as the first egg is laid, so the brood hatches asynchronously, beginning 33 to 34 days later. The first hatchling typically has a competitive edge over the others. While stronger chicks are not aggressive towards weaker siblings, as is the case in some species, weak or small chicks are sometimes killed by their parents. This behaviour occurs in times of food shortage to reduce brood size and hence increase the chance of survival of the remaining nestlings. White Stork nestlings do not attack each other, and their parents' method of feeding them (disgorging large amounts of food at once) means that stronger siblings cannot outcompete weaker ones for food directly, hence parental infanticide is an efficient way of reducing brood size. Despite this, this behaviour has not commonly been observed.
The temperature and weather around the time of hatching in spring is important; cool temperatures and wet weather increase chick mortality and reduce breeding success rates. Somewhat unexpectedly, studies have found that later-hatching chicks which successfully reach adulthood produce more chicks than do their earlier-hatching nestmates. The body weight of the chicks increases rapidly in the first few weeks and reaches a plateau of about 3.4 kg (7.5 lb) in 45 days. The length of the beak increases linearly for about 50 days. Young birds are fed with earthworms and insects, which are regurgitated by the parents onto the floor of the nest. Older chicks reach into the mouths of parents to obtain food. Chicks fledge 58 to 64 days after hatching.
White Storks generally begin breeding when about four years old, although the age of first breeding has been recorded as early as two years and as late as seven years. The oldest known wild White Stork lived for 39 years after being ringed
in Switzerland, while captive birds have lived for more than 35 years.
s for an array of small arthropods, particularly over the warmer months after the birds arrive to breed. Nesting over successive years, the storks bring more material to line their nests and layers of organic material accumulate within them. Not only do their bodies tend to regulate temperatures within the nest, but excrement, food remains and feather and skin fragments provide nourishment for a large and diverse population of free-living mesostigmatic
mites. A survey of twelve nests found 13,352 individuals of 34 species, the most common being Macrocheles merdarius, M. robustulus, Uroobovella pyriformis and Trichouropoda orbicularis, which together represented almost 85% of all the specimens collected. These feed on the eggs and larvae of insects and on nematode
s, which are abundant in the nest litter. These mites are dispersed by coprophilous
beetles, often of the family Scarabaeidae
, or on dung brought by the storks during nest construction. Parasitic mites do not occur, perhaps being controlled by the predatory species. The overall impact of the mite population is unclear, the mites may have a role in suppressing harmful organisms (and hence be beneficial), or they may themselves have an adverse effect on nestlings.
The birds themselves host species belonging to more than four genera of feather mites. These mites, including Freyana pelargica, Pterolichus ciconiae and Xoloptes didactylus live on fungi growing on the feathers. The fungi found on the plumage may feed on the keratin
of the outer feathers or on feather oil. Chewing lice such as Colpocephalum zebra tend to be found on the wings, and Neophilopterus incompletus elsewhere on the body.
The White Stork also carries several types of internal parasites, including Toxoplasma gondii
and intestinal parasite
s of the genus Giardia
. A study of 120 White Stork carcasses from Saxony-Anhalt
and Brandenburg
in Germany yielded eight species of trematode
(fluke), four cestode
(tapeworm) species, and at least three species of nematode. One species of fluke, Chaunocephalus ferox, caused lesions in the wall of the small intestine in a number of birds admitted to two rehabilitation centers in central Spain, and was associated with reduced weight. It is a recognised pathogen and cause of morbidity in the Asian Openbill (Anastomus oscitans).
West Nile virus
(WNV) is mainly a bird infection that is transmitted between birds by mosquito
s. Migrating birds appear to be important in spread of the virus, the ecology of which remains poorly known. On 26 August 1998, a flock of about 1,200 migrating White Storks that had been blown off course on their southward journey landed in Eilat, in southern Israel. The flock was stressed as it had resorted to flapping flight to return to its migratory route, and a number of birds died. A virulent strain of West Nile virus was isolated from the brains of eleven dead juveniles. Other White Storks subsequently tested in Israel have shown anti-WNV antibodies
. In 2008 three juvenile White Storks from a Polish wildlife refuge yielded seropositive
results indicating exposure to the virus, but the context or existence of the virus in that country is unclear.
and agricultural changes (principally the draining of wetlands and conversion of meadows to crops such as maize
) began in the 19th century: the last wild individual in Belgium was seen in 1895, in Sweden in 1955, in Switzerland in 1950 and in Holland in 1991. However, the species has since been reintroduced to many regions. It has been rated as Least Concern by the IUCN since 1994, after being evaluated as Near Threatened
in 1988. The White Stork is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA
) applies. Parties to the Agreement are required to engage in a wide range of conservation strategies described in a detailed action plan. The plan is intended to address key issues such as species and habitat conservation, management of human activities, research, education, and implementation. Threats include the continued loss of wetlands, collisions with overhead power lines, use of persistent pesticides
(such as DDT
) to combat locust
s in Africa, and largely illegal hunting on migration routes and wintering grounds.
A large population of White Storks breeds in central and eastern Europe. In a 2004 census, there were 52,500 pairs in Poland, 12,000–18,000 pairs in Ukraine, 10,500–13,000 pairs in Belarus
, 10,000 pairs in Lithuania (the highest known density of this species in the world), and 8,500 pairs in Latvia. In Estonia the population has also been increasing, numbering about 4,000 pairs in 2004. There were around 5,000 pairs in Romania and an estimated 4,818 breeding pairs in Bulgaria. In Germany, 3,000 of the total 3,400 pairs are in the former East Germany. Apart from Spain and Portugal (33,217 pairs and 7,684 pairs in 2004/05 respectively), populations in western Europe are generally much less stable; for instance, the once sizable Danish population declined to just three pairs in 2005.
In the 1980s, the population had fallen to fewer than nine pairs in the entire upper Rhine River valley, an area closely identified with the White Stork for centuries. Conservation efforts successfully increased the population of birds there to 270 pairs, largely due to the actions of the Association for the Protection and Reintroduction of Storks in Alsace
and Lorraine
. The reintroduction of zoo
-reared birds has halted further declines in Italy (30 pairs), the Netherlands (9–12 pairs), and Switzerland (120–160 pairs). There were 601 pairs breeding in Armenia and around 700 pairs in the Netherlands in 2008, and few pairs also breed in South Africa, typically recent colonists from within the normal wintering population. In Poland, electric poles have been modified with a platform at the top to prevent the White Stork's large nest from disrupting the electricity supply, and sometimes nests are moved from an electric pole to a man-made platform. Introductions of zoo-reared birds in the Netherlands has been followed up by feeding and nest-building programs by volunteers. Similar reintroduction programs are taking place in Sweden, and Switzerland, where 175 pairs were recorded breeding in 2000. Long term viability of the population in Switzerland is unclear as breeding success rates are low, and supplementary feeding does not appear to be of benefit.
, it was associated with, and was the hieroglyph for, the Ba, or "soul". The Hebrew word for the White Stork is chasidah (חסידה), meaning "merciful" or "kind". Greek
and Roman mythology
portray storks as models of parental devotion, and it was believed that they did not die of old age, but flew to islands and took the appearance of humans. The bird is featured in two of Aesop's Fables
: The Fox and the Stork and The Farmer and the Stork
. They were also thought to care for their aged parents, feeding them and even transporting them, and children's books depicted them as a model of filial values. A Greek law called Pelargonia, from the Ancient Greek
word pelargos for stork, required citizens to take care of their aged parents. The Greeks also held that killing a stork could be punished with death. It was allegedly protected in Ancient Thessaly
as it hunted snakes, and widely held to be Virgil
's "white bird". Roman writers noted the White Stork's arrival in spring, which alerted farmers to plant their vines.
Followers of Islam
revered storks because they made an annual pilgrimage to Mecca
on their migration. Some of the earliest understanding on bird migration were initiated by an interest in White Storks; Pfeilstorch
("arrow storks") were found in Europe with African arrow
s embedded in their bodies. A well-known example of such a stork found in the summer of 1822 in the German town of Klütz
in Mecklenburg
was made into a mounted taxidermy specimen, complete with the ornate African arrow, that is now in the University of Rostock
.
Storks have little fear of humans if not disturbed, and often nest on buildings in Europe. In Germany, the presence of a nest on a house was believed to protect against fires. They were also protected because of the belief that their souls were human. German and Dutch households would encourage storks to nest on houses, sometimes by constructing purpose-built high platforms, to bring good luck. Poles, Lithuanians and Ukrainians believe that storks bring harmony to a family on whose property they nest.
The White Stork is a popular motif on postage stamp
s, and it is featured on more than 120 stamps issued by more than 60 stamp-issuing entities. It is the national bird of Lithuania, and it was a Polish mascot at the Expo 2000
Fair in Hanover. In the 19th century, storks were also thought to only live in countries having a republican form of government. Polish poet Cyprian Kamil Norwid mentioned storks in his poem Moja piosnka (II) ("My Song (II)"):
story called The Storks. German folklore held that storks found babies in caves or marshes and brought them to households in a basket on their backs or held in their beaks. These caves contained adebarsteine or "stork stones". The babies would then be given to the mother or dropped down the chimney. Households would notify when they wanted children by placing sweets for the stork on the window sill. From there the folklore has spread around the world to countries such as the Philippines and South America.
In Slavic mythology and religion
, storks were thought to carry unborn souls from Iriy
to Earth in spring and summer. This belief still persists in the modern folk culture of many Slavic countries, in the simplified child story that "storks bring children into the world". Storks were seen by the Slavs as bringing luck, and killing one would bring misfortune. A long-term study that showed a spurious correlation between the numbers of stork nests and human births is widely used in the teaching of basic statistics
as an example to highlight that correlation does not necessarily indicate causation
. The child-bringing myth has appeared in different forms in history. Children of African American
slaves were sometimes told that white babies were brought by storks, while black babies were born from buzzard eggs.
Psychoanalyst Marvin Margolis suggests the enduring nature of the stork fable of the newborn is linked to its addressing a psychological need, in that it allays the discomfort of discussing sex and procreation with children. Birds have long been associated with the maternal symbols from pagan goddesses such as Juno
to the Holy Ghost
, and the stork may have been chosen for its white plumage (depicting purity), size (in that it is big enough to carry an infant), and flight at high altitude (likened to flying between Earth and Heaven). The fable and its relation to the internal world of the child have been discussed by Sigmund Freud
, and Carl Jung
. In fact, Jung recalled being told the story himself upon the birth of his own sister. The traditional link with the newborn continues with their use in advertising
for such products as nappies
and birth announcements
.
There were negative aspects to stork folklore as well; a Polish folk tale relates how God made the stork's plumage white, while the Devil gave it black wings, imbuing it with both good and evil impulses. They were also associated with handicapped or stillborn babies in Germany, explained as the stork having dropped the baby en route to the household, or as revenge or punishment for past wrongdoing. A mother who was confined to bed around the time of childbirth was said to have been "bitten" by the stork. In Denmark, storks were said to toss a nestling off the nest and then an egg in successive years. In medieval England, storks were also associated with adultery, possibly inspired by their courtship rituals. Their preening and posture saw them linked with the attribute of self-conceit.
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
in the stork
Stork
Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family Ciconiidae. They are the only family in the biological order Ciconiiformes, which was once much larger and held a number of families....
family Ciconiidae. Its plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
is mainly white, with black on its wings. Adults have long red legs and long pointed red beaks, and measure on average 100 – from beak tip to end of tail, with a 195 – wingspan. The two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
, which differ slightly in size, breed in Europe (north to Estonia
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...
), northwestern Africa, southwestern Asia (east to southern Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
), and southern Africa. The White Stork is a long-distance migrant
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, wintering in Africa from tropical Sub-Saharan Africa
Sub-Saharan Africa
Sub-Saharan Africa as a geographical term refers to the area of the African continent which lies south of the Sahara. A political definition of Sub-Saharan Africa, instead, covers all African countries which are fully or partially located south of the Sahara...
to as far south as South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, or on the Indian subcontinent
Indian subcontinent
The Indian subcontinent, also Indian Subcontinent, Indo-Pak Subcontinent or South Asian Subcontinent is a region of the Asian continent on the Indian tectonic plate from the Hindu Kush or Hindu Koh, Himalayas and including the Kuen Lun and Karakoram ranges, forming a land mass which extends...
. When migrating between Europe and Africa, it avoids crossing the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
and detours via the Levant
Levant
The Levant or ) is the geographic region and culture zone of the "eastern Mediterranean littoral between Anatolia and Egypt" . The Levant includes most of modern Lebanon, Syria, Jordan, Israel, the Palestinian territories, and sometimes parts of Turkey and Iraq, and corresponds roughly to the...
in the east or the Strait of Gibraltar
Strait of Gibraltar
The Strait of Gibraltar is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Spain in Europe from Morocco in Africa. The name comes from Gibraltar, which in turn originates from the Arabic Jebel Tariq , albeit the Arab name for the Strait is Bab el-Zakat or...
in the west, because the air thermals on which it depends do not form over water.
A carnivore
Carnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
, the White Stork eats a wide range of animal prey, including insects, fish, amphibians, reptiles, small mammals, and small birds. It takes most of its food from the ground, among low vegetation, and from shallow water. It is a monogamous breeder, but does not pair for life. Both members of the pair build a large stick nest, which may be used for several years. Each year the female can lay one clutch
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
of usually four eggs, which hatch asynchronously 33–34 days after being laid. Both parents take turns incubating the eggs and both feed the young. The young leave the nest 58–64 days after hatching, and continue to be fed by the parents for a further 7–20 days.
The White Stork has been rated as Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
by the International Union for Conservation of Nature (IUCN). It benefited from human activities during the Middle Ages
Middle Ages
The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...
as woodland was cleared, but changes in farming methods and industrialisation saw it decline and disappear from parts of Europe in the 19th and early 20th centuries. Conservation and reintroduction
Reintroduction
Reintroduction is the deliberate release of a species into the wild in zones formerly inhabited by said species but where it has disappeared from for a number of reasons, from captivity or relocated from other areas where the species still survives in...
programs across Europe have resulted in the White Stork resuming breeding in the Netherlands, Switzerland, and Sweden. It has few natural predators, but may harbour several types of parasite; the plumage is home to chewing lice
Chewing louse
Mallophaga is a suborder of lice, known as chewing lice, biting lice or bird lice, containing more than 3000 species. They have paurometabolis or incomplete metamorphosis....
and feather mites, while the large nests maintain a diverse range of mesostigmatic
Mesostigmata
Mesostigmata is an order of mites belonging to the Parasitiformes. Unlike most members of that group, many of these mites are not parasitic but free-living and predatory. They can be recognized by the single pair of spiracles positioned laterally on the body....
mites. This conspicuous bird has given rise to many legends across its range, of which the best-known is the story of babies being brought by storks.
Taxonomy and evolution
The White Stork was one of the many bird species originally describedAves in the 10th edition of Systema Naturae
In the 10th edition of Systema Naturae, Carl Linnaeus listed the 564 species of bird from around the world which were known to him at the time. There are now believed to be around 10,000 extant species...
by Linnaeus
Carolus Linnaeus
Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
in the landmark 1758 10th edition
10th edition of Systema Naturae
The 10th edition of Systema Naturae was a book written by Carl Linnaeus and published in two volumes in 1758 and 1759, which marks the starting point of zoological nomenclature...
of his Systema Naturae
Systema Naturae
The book was one of the major works of the Swedish botanist, zoologist and physician Carolus Linnaeus. The first edition was published in 1735...
, where it was given the binomial name of Ardea ciconia. It was reclassified to (and was designated the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
of) the new genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Ciconia
Ciconia
Ciconia is a genus of birds in the stork family. Six of the seven living species occur in the Old World, but the Maguari Stork has a South American range. In addition, fossils suggest that Ciconia storks were somewhat more common in the tropical Americas in prehistoric times.These are large storks,...
by French zoologist Mathurin Jacques Brisson
Mathurin Jacques Brisson
Mathurin Jacques Brisson was a French zoologist and natural philosopher.Brisson was born at Fontenay-le-Comte. The earlier part of his life was spent in the pursuit of natural history, his published works in this department including Le Règne animal and Ornithologie...
in 1760. Both the genus and specific epithet, cǐcōnia, are the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
word for "stork", originally recorded in the works of Horace
Horace
Quintus Horatius Flaccus , known in the English-speaking world as Horace, was the leading Roman lyric poet during the time of Augustus.-Life:...
and Ovid
Ovid
Publius Ovidius Naso , known as Ovid in the English-speaking world, was a Roman poet who is best known as the author of the three major collections of erotic poetry: Heroides, Amores, and Ars Amatoria...
. The word stork is derived from the Old English word storc, and appeared in the tenth-century works the Erfurt Glossary, where the word is equated with Ciconia, and Aelfric's
Ælfric of Eynsham
Ælfric of Eynsham was an English abbot, as well as a consummate, prolific writer in Old English of hagiography, homilies, biblical commentaries, and other genres. He is also known variously as Ælfric the Grammarian , Ælfric of Cerne, and Ælfric the Homilist...
Homilies. The word is related to the Old High German
Old High German
The term Old High German refers to the earliest stage of the German language and it conventionally covers the period from around 500 to 1050. Coherent written texts do not appear until the second half of the 8th century, and some treat the period before 750 as 'prehistoric' and date the start of...
storah, "stork", and similar words in many other European languages, all of which are descended from the Teutonic
Germanic languages
The Germanic languages constitute a sub-branch of the Indo-European language family. The common ancestor of all of the languages in this branch is called Proto-Germanic , which was spoken in approximately the mid-1st millennium BC in Iron Age northern Europe...
sturko-z.
There are two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
:
- C. c. ciconia, the nominate subspecies described by Linnaeus in 1758, breeds from Europe to northwest Africa and westernmost Asia, and in southern Africa, and winters mainly in Africa south of the Sahara Desert, though some birds winter in India.
- C. c. asiatica, described by Russian naturalist Nikolai Severtzov in 1873, breeds in TurkestanTurkestanTurkestan, spelled also as Turkistan, literally means "Land of the Turks".The term Turkestan is of Persian origin and has never been in use to denote a single nation. It was first used by Persian geographers to describe the place of Turkish peoples...
and winters from Iran to India. It is slightly larger than the nominate subspecies.
The stork family contains six genera in three broad groups: the open-billed and wood storks (Mycteria
Mycteria
Mycteria is a genus of large tropical storks with representatives in the Americas, east Africa and southern and southeastern Asia. Two species have "ibis" in their scientific or old common names, but they are not related to these birds and simply look more similar to an ibis than do other...
and Anastomus), the giant storks (Ephippiorhynchus
Ephippiorhynchus
Ephippiorhynchus is a small genus of storks. It contains two living species only, very large birds more than 140 cm tall with a 230–270 cm wingspan. Both are mainly black and white, with huge colourful, mainly red and black bills. The sexes of these species are similarly plumaged, but...
, Jabiru
Jabiru
The Jabiru is a large stork found in the Americas from Mexico to Argentina, except west of the Andes. It is most common in the Pantanal region of Brazil and the Eastern Chaco region of Paraguay. It is the only member of the genus Jabiru...
and Leptoptilos
Leptoptilos
Leptoptilos is a genus of very large tropical storks. Two species are resident breeders in southern Asia, and the Marabou Stork is found in sub-Saharan Africa....
), and the "typical" storks, Ciconia
Ciconia
Ciconia is a genus of birds in the stork family. Six of the seven living species occur in the Old World, but the Maguari Stork has a South American range. In addition, fossils suggest that Ciconia storks were somewhat more common in the tropical Americas in prehistoric times.These are large storks,...
. The typical storks include the White Stork and six other extant species, which are characterised by straight pointed beaks and mainly black and white plumage. Its closest relatives are the larger, black-billed Oriental White Stork (Ciconia boyciana) of East Asia
East Asia
East Asia or Eastern Asia is a subregion of Asia that can be defined in either geographical or cultural terms...
, which was formerly classified as a subspecies of the White Stork, and the Maguari Stork
Maguari Stork
The Maguari Stork is a species of stork in the Ciconiidae family.It is found in Argentina, Bolivia, Brazil, Colombia, French Guiana, Guyana, Paraguay, Suriname, Uruguay, and Venezuela. It is a vagrant to Chile, Trinidad, the Falkland Islands and probably Peru...
(C. maguari) of South America. Close evolutionary relationships within Ciconia are suggested by behavioural similarities and, biochemically, through analysis of both mitochondrial cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
gene sequences and DNA-DNA hybridization.
Fossil record
A Ciconia fossil representing the distal end of a right humerusHumerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
has been recovered from Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
beds of Rusinga Island
Rusinga Island
Rusinga Island, with an elongated shape approx. 10 miles from end to end and 3 miles at its widest point, lies in the eastern part of Lake Victoria at the mouth of the Winam Gulf...
, Lake Victoria, Kenya. The 24–6 million year old fossil could have originated from either a White Stork or a Black Stork
Black Stork
The Black Stork Ciconia nigra is a large wading bird in the stork family Ciconiidae. It is a widespread, but rare, species that breeds in the warmer parts of Europe, predominantly in central and eastern regions. This is a shy and wary species, unlike the closely related White Stork. It is seen in...
(C. nigra), which are species of about the same size with very similar bone structures. The Middle Miocene
Middle Miocene
The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene....
beds of Maboko Island
Maboko Island
Maboko Island is a small island lying in the Winam Gulf of Lake Victoria, in Nyanza Province of western Kenya. It is about 1.8 km long by 1 km wide. It is an important Middle Miocene paleontological site with fossiliferous deposits that were discovered in the 1930s...
have yielded further remains.
Description
The White Stork is a large bird. It has a length of 100 –,By convention, length is measured from the tip of the bill to the tip of the tail on a dead bird (or skin) laid on its back., a standing height of 100–125 cm (39.4–49.2 in), a wingspan of 195 –, and a weight of 2.3 –. Like all storks, it has long legs, a long neck, and a long, straight, pointed beakBeak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
. The sexes are identical in appearance, except that males are larger than females on average. The plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
is mainly white with black flight feather
Flight feather
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired feathers on the wings or tail of a bird; those on the wings are called remiges while those on the tail are called rectrices . Their primary function is to aid in the generation of both thrust and lift, thereby...
s and wing coverts
Covert (feather)
A covert feather on a bird is one of a set of feathers, called coverts, which as the name implies, cover other feathers. The coverts help to smooth airflow over the wings and tail.- Wing-coverts :...
; the black is caused by the pigment melanin
Melanin
Melanin is a pigment that is ubiquitous in nature, being found in most organisms . In animals melanin pigments are derivatives of the amino acid tyrosine. The most common form of biological melanin is eumelanin, a brown-black polymer of dihydroxyindole carboxylic acids, and their reduced forms...
. The breast feathers are long and shaggy forming a ruff which is used in some courtship displays. The irises
Iris (anatomy)
The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...
are dull brown or grey, and the peri-orbital
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents...
skin is black. The adult has a bright red beak and red legs, the coloration of which is derived from carotenoid
Carotenoid
Carotenoids are tetraterpenoid organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some bacteria, and some types of fungus. Carotenoids can be synthesized fats and other basic organic metabolic building...
s in the diet. In parts of Spain, studies have shown that the pigment is based on astaxanthin
Astaxanthin
Astaxanthin is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes. It is classified as a xanthophyll, which means "yellow leaves". Like many carotenoids, it is a colorful, lipid-soluble pigment. Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp,...
obtained from an introduced species of crayfish (Procambarus clarkii
Procambarus clarkii
Procambarus clarkii is a freshwater crayfish species, native to the Southeastern United States, but found also on other continents, where it is often an invasive pest. It is known variously as the red swamp crawfish, red swamp crayfish, Louisiana crawfish, Louisiana crayfish or mudbug.-Range and...
) and the bright red beak colours show up even in nestlings, in contrast to the duller beaks of young White Storks elsewhere.
As with other storks, the wings are long and broad enabling the bird to soar. In flapping flight
Bird flight
Flight is the main mode of locomotion used by most of the world's bird species. Flight assists birds while feeding, breeding and avoiding predators....
its wingbeats are slow and regular. It flies with its neck stretched forward and with its long legs extended well beyond the end of its short tail. It walks at a slow and steady pace with its neck upstretched. In contrast, it often hunches its head between its shoulders when resting. Moulting has not been extensively studied, but appears to take place throughout the year, with the primary flight feathers replaced over the breeding season.
Upon hatching, the young White Stork is partly covered with short, sparse, whitish down feather
Down feather
The down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down. Powder down is a specialized type of down found only in a few groups of birds. Down is a fine thermal insulator and padding, used in goods such as jackets, bedding,...
s. This early down is replaced about a week later with a denser coat of woolly white down. By three weeks, the young bird acquires black scapulars and flight feather
Flight feather
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired feathers on the wings or tail of a bird; those on the wings are called remiges while those on the tail are called rectrices . Their primary function is to aid in the generation of both thrust and lift, thereby...
s. On hatching the chick has pinkish legs, which turn to greyish-black as it ages. Its beak is black with a brownish tip. By the time it fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
s, the juvenile bird's plumage is similar to that of the adult, though its black feathers are often tinged with brown, and its beak and legs are a duller brownish-red or orange. The beak is typically orange or red with a darker tip. The bills gain the adults' red colour the following summer, although the black tips persist in some individuals. Young storks adopt adult plumage by their second summer.
Similar species
Within its range the White Stork is distinctive when seen on the ground but, when seen at a distance in flight, it can be confused with several other species with similar underwing patterns, such as the Yellow-billed StorkYellow-billed Stork
The Yellow-billed Stork, Mycteria ibis, is a large wading bird in the stork family Ciconiidae. It occurs in Africa south of the Sahara and in Madagascar....
, Great White Pelican, and Egyptian Vulture
Egyptian Vulture
The Egyptian Vulture is a small Old World vulture, found widely distributed from southwestern Europe and northern Africa to southern Asia. It is the only living member of the genus Neophron. It has sometimes also been known as the White Scavenger Vulture or Pharaoh's Chicken...
. The Yellow-billed Stork is identified by its black tail and a longer, slightly curved, yellow beak. The Great White Pelican has short legs which do not extend beyond its tail, and it flies with its neck retracted, keeping its head near to its stocky body, giving it a different flight profile. Pelicans also behave differently, soaring in orderly, synchronised flocks rather than in disorganised groups of individuals as the White Stork does. The Egyptian Vulture is much smaller, with a long wedge-shaped tail, shorter legs and a small yellow-tinged head on a short neck. The Common Crane
Common Crane
The Common Crane , also known as the Eurasian Crane, is a bird of the family Gruidae, the cranes.It is a large, stately bird and a medium-sized crane at 100–130 cm long, with a 180–240 cm wingspan and a weight of 4.5–6 kg...
, which can also look black and white in strong light, shows longer legs and a longer neck in flight.
Distribution and habitat
The nominate race of the White Stork has a wide although disjunct summer range across Europe, clustered in the Iberian PeninsulaIberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...
and North Africa in the west, and much of eastern and central Europe, with 25 percent of the world's population concentrated in Poland, as well as parts of western Asia. The asiatica population of about 1450 birds is restricted to a region in central Asia between the Aral Sea
Aral Sea
The Aral Sea was a lake that lay between Kazakhstan in the north and Karakalpakstan, an autonomous region of Uzbekistan, in the south...
and Xinjiang
Xinjiang
Xinjiang is an autonomous region of the People's Republic of China. It is the largest Chinese administrative division and spans over 1.6 million km2...
in western China. The Xinjiang population is believed to have become extinct around 1980. Migration
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
routes extend the range of this species into many parts of Africa and India. Some populations adhere to the eastern migration route, which passes across Israel into eastern and central Africa.
A few records of breeding from South Africa have been known since 1933 at Calitzdorp, and about 10 birds have been known to breed since the 1990s around Bredasdorp
Bredasdorp
Bredasdorp is a town in the Southern Overberg region of the Western Cape, South Africa, and the main economic and service hub of that region. It lies on the northern edge of the Agulhas Plain, about south-east of Cape Town and north of Cape Agulhas, the southernmost tip of Africa.-History:The...
. A small population of White Storks winters in India and is thought to derive principally from the C. c. asiatica population as flocks of up to 200 birds have been observed on spring migration in the early 1900s through the Kurram Valley
Kurram Valley
Kurram tribal agency is located in the FATA area of Pakistan. Geographically it covers Kurram Valley which is a beautiful valley in the northwestern part of Pakistan neighboring Afghanistan....
. However, birds ringed
Bird ringing
Bird ringing or bird banding is a technique used in the study of wild birds, by attaching a small, individually numbered, metal or plastic tag to their legs or wings, so that various aspects of the bird's life can be studied by the ability to re-find the same individual later...
in Germany have been recovered in western (Bikaner) and southern (Tirunelveli
Tirunelveli District
Tirunelveli District is a district of Tamil Nadu state in southern India. The city of Tirunelveli is the district headquarters. A unique feature of this district is that it encompasses all five geographical traditions of Tamil Literature; kurinji , mullai , marudham , neithal and palai...
) India. An atypical specimen with red orbital skin, a feature of the Oriental White Stork, has been recorded and further study of the Indian population is required. North of the breeding range, it is a passage migrant or vagrant
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...
in Finland, Great Britain, Iceland, Ireland, Norway, and Sweden, and west to the Azores
Azores
The Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
and Madeira
Madeira
Madeira is a Portuguese archipelago that lies between and , just under 400 km north of Tenerife, Canary Islands, in the north Atlantic Ocean and an outermost region of the European Union...
. In recent years, the range has expanded into western Russia.
The White Stork's preferred feeding grounds are grassy meadows, farmland and shallow wetlands. It avoids areas overgrown with tall grass and shrub. In the Chernobyl area of northern Ukraine, White Stork populations declined after the 1986 nuclear accident
Chernobyl disaster
The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine , which was under the direct jurisdiction of the central authorities in Moscow...
there as farmland was succeeded
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
by tall grass shrub. In parts of Poland, poor natural foraging grounds have forced birds to seek food at rubbish dump
Landfill
A landfill site , is a site for the disposal of waste materials by burial and is the oldest form of waste treatment...
s since 1999. White Storks have also been reported foraging in rubbish dumps in the Middle East, North Africa, and South Africa.
The White Stork breeds in greater numbers in areas with open grasslands, particularly grassy areas which are wet or periodically flooded, and less in areas with taller vegetation cover such as forest and shrubland. They make use of grasslands, wetlands, and farmland on the wintering grounds in Africa. White Storks were probably aided by human activities during the Middle Ages
Middle Ages
The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...
as woodland was cleared and new pastures and farmland were created, and they were found across much of Europe, breeding as far north as Sweden. The White Stork is a rare visitor to the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...
, though in 1416 a pair nested atop St Giles's Church in Edinburgh
Edinburgh
Edinburgh is the capital city of Scotland, the second largest city in Scotland, and the eighth most populous in the United Kingdom. The City of Edinburgh Council governs one of Scotland's 32 local government council areas. The council area includes urban Edinburgh and a rural area...
, Scotland. A decline in population began in the 19th century due to industrialisation
Industrialisation
Industrialization is the process of social and economic change that transforms a human group from an agrarian society into an industrial one...
and changes in agricultural methods. White Storks no longer nest in many countries, and the current strongholds of the western population are in Spain, Ukraine, and Poland. In the Iberian Peninsula, populations are concentrated in the southwest, and have also declined due to agricultural practices. A study published in 2005 found that the Podhale
Podhale
The Podhale is Poland's most southern region, sometimes referred to as the "Polish highlands". The Podhale is located in the foothills of the Tatra range of the Carpathian mountains, and is characterized by a rich tradition of folklore that is much romanticized in the Polish patriotic imagination...
region in the uplands of southern Poland had seen an influx of White Storks, which first bred there in 1931 and have nested at progressively higher altitudes since, reaching 890 m (3000 ft) in 1999. The authors proposed that this was related to climate warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
, and the influx of other animals and plants to higher altitudes. White Storks arriving in Poznań province in western Poland in spring to breed did so some 10 days earlier in the last twenty years of the 20th century than at the end of the 19th century.
Migration
Systematic research into migration began with GermanGermany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
ornithologist Johannes Thienemann
Johannes Thienemann
Johannes Thienemann was a German ornithologist and a pioneer bird bander who established the Rossitten Bird Observatory, the world’s first....
who commenced ringing studies in 1906 at the Rossitten Bird Observatory
Rossitten Bird Observatory
The Rossitten Bird Observatory was the world's first ornithological observatory. It was sited at Rossitten, East Prussia , on the Curonian Spit on the south-eastern coast of the Baltic Sea...
, on the Curonian Spit
Curonian Spit
The Curonian Spit is a 98 km long, thin, curved sand-dune spit that separates the Curonian Lagoon from the Baltic Sea coast. Its southern portion lies within Kaliningrad Oblast, Russia and its northern within southwestern Lithuania...
in what was then East Prussia
East Prussia
East Prussia is the main part of the region of Prussia along the southeastern Baltic Coast from the 13th century to the end of World War II in May 1945. From 1772–1829 and 1878–1945, the Province of East Prussia was part of the German state of Prussia. The capital city was Königsberg.East Prussia...
. Although not many storks passed through Rossitten itself, the observatory coordinated the large-scale ringing of the species throughout Germany and elsewhere in Europe. Between 1906 and the Second World War
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
about 100,000, mainly juvenile, White Storks were ringed, with over 2,000 long-distance recoveries of birds wearing Rossitten rings reported between 1908 and 1954.
Routes
White Storks fly south from their summer breeding grounds in Europe in August and September, heading for Africa. There, they spend the winter in savannaSavanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
from Kenya and Uganda south to the Cape Province
Cape Province
The Province of the Cape of Good Hope was a province in the Union of South Africa and subsequently the Republic of South Africa...
of South Africa. In these areas they congregate in large flocks which may exceed a thousand individuals. Some diverge westwards into western Sudan and Chad, and may reach Nigeria. In spring, the birds return north; they are recorded from Sudan and Egypt from February to April. They arrive back in Europe around late March and April, after an average journey of 49 days. By comparison, the autumn journey is completed in about 26 days. Tailwind
Tailwind
A tailwind is a wind that blows in the direction of travel of an object, while a headwind blows against the direction of travel. A tailwind increases the object's speed and reduces the time required to reach its destination, while a headwind has the opposite effect...
s and scarcity of food and water en route (birds fly faster over regions lacking resources) increase average speed.
To avoid a long sea crossing over the Mediterranean, birds from central Europe either follow an eastern migration route by crossing the Bosphorus to Turkey, traversing the Levant
Levant
The Levant or ) is the geographic region and culture zone of the "eastern Mediterranean littoral between Anatolia and Egypt" . The Levant includes most of modern Lebanon, Syria, Jordan, Israel, the Palestinian territories, and sometimes parts of Turkey and Iraq, and corresponds roughly to the...
, then bypassing the Sahara Desert by following the Nile
Nile
The Nile is a major north-flowing river in North Africa, generally regarded as the longest river in the world. It is long. It runs through the ten countries of Sudan, South Sudan, Burundi, Rwanda, Democratic Republic of the Congo, Tanzania, Kenya, Ethiopia, Uganda and Egypt.The Nile has two major...
valley southwards, or follow a western route over the Strait of Gibraltar
Strait of Gibraltar
The Strait of Gibraltar is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Spain in Europe from Morocco in Africa. The name comes from Gibraltar, which in turn originates from the Arabic Jebel Tariq , albeit the Arab name for the Strait is Bab el-Zakat or...
. These migration corridors maximise help from the thermals and thus save energy. The eastern route is by far the more important with 530,000 White Storks using it annually, making the species the second commonest migrant there (after the Honey Buzzard
Honey Buzzard
The European Honey Buzzard , is a bird of prey in the family Accipitridae which also includes many other diurnal raptors such as kites, eagles and harriers....
). The flocks of migrating raptor
Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....
s, White Storks and Great White Pelicans can stretch for 200 km (125 mi). The eastern route is twice as long as the western, but storks take the same time to reach the wintering grounds by either.
Juvenile White Storks set off on their first southward migration in an inherited direction but, if displaced from that bearing by weather conditions, they are unable to compensate, and may end up in a new wintering location. Adults can compensate for strong winds and adjust their direction to finish at their normal winter sites, because they are familiar with the location. For the same reason, all spring migrants, even those from displaced wintering locations, can find their way back to the traditional breeding sites. An experiment with young birds raised in captivity in Kaliningrad and released in the absence of wild storks to show them the way revealed that they appeared to have an instinct to fly south, although the scatter in direction was large.
Energetics
White Storks rely on the uplift of air thermalThermal
A thermal column is a column of rising air in the lower altitudes of the Earth's atmosphere. Thermals are created by the uneven heating of the Earth's surface from solar radiation, and are an example of convection. The sun warms the ground, which in turn warms the air directly above it...
s to soar and glide the long distances of their annual migrations between Europe and Sub-Saharan Africa
Sub-Saharan Africa
Sub-Saharan Africa as a geographical term refers to the area of the African continent which lies south of the Sahara. A political definition of Sub-Saharan Africa, instead, covers all African countries which are fully or partially located south of the Sahara...
. For many, the shortest route would take them over the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
; however, since air thermals do not form over water, they generally detour over land to avoid the trans-Mediterranean flights that would require prolonged energetic wing flapping. It has been estimated that flapping flight metabolises 23 times more body fat than soaring flight per distance travelled. Thus, flocks spiral upwards on rising warm air until they emerge at the top, up to 1200–1500 m (4000–5000 ft) above the ground (though one record from Western Sudan observed an altitude of 3300 m (10,800 ft)).
Long flights over water may occasionally be undertaken. A young White Stork ringed
Bird ringing
Bird ringing or bird banding is a technique used in the study of wild birds, by attaching a small, individually numbered, metal or plastic tag to their legs or wings, so that various aspects of the bird's life can be studied by the ability to re-find the same individual later...
at the nest in Denmark subsequently appeared in England, where it spent some days before moving on. It was later seen flying over St Mary's, Isles of Scilly, and arrived in a poor condition in Madeira
Madeira
Madeira is a Portuguese archipelago that lies between and , just under 400 km north of Tenerife, Canary Islands, in the north Atlantic Ocean and an outermost region of the European Union...
three days later. That island is 500 km (320 mi) from Africa, and twice as far from the European mainland. Migration through the Middle East
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
may be hampered by the khamsin
Khamsin
Khamsin, khamseen, chamsin or hamsin , also known as khamaseen refers to a dry, hot and dusty local wind blowing in North Africa and the Arabian Peninsula. Similar winds in the area are sirocco and simoom...
, winds bringing gusty overcast days unsuitable for flying. In these situations, flocks of White Storks sit out the adverse weather on the ground, standing and facing into the wind.
Behaviour
The White Stork is a gregarious bird; flocks of thousands of individuals have been recorded on migration routes and at wintering areas in Africa. Non-breeding birds gather in groups of 40 or 50 during the breeding season. The smaller dark-plumaged Abdim's StorkAbdim's Stork
The Abdim's Stork, also known as White-bellied Stork, is a black stork with grey legs, red knees and feet, grey bill and white underparts. It has red facial skin in front of eye and blue skin near the bill in breeding season...
is often encountered with White Stork flocks in southern Africa. Breeding pairs of White Stork may gather in small groups to hunt, and colony nesting has been recorded in some areas. However, groups among White Stork colonies vary widely in size and the social structure is loosely defined; young breeding storks are often restricted to peripheral nests, while older storks attain higher breeding success while occupying the better quality nests toward the centres of breeding colonies. Social structure and group cohesion is maintained by altruistic
Altruism
Altruism is a concern for the welfare of others. It is a traditional virtue in many cultures, and a core aspect of various religious traditions, though the concept of 'others' toward whom concern should be directed can vary among cultures and religions. Altruism is the opposite of...
behaviours such as allopreening
Personal grooming
Personal grooming is the art of cleaning, grooming, and maintaining parts of the body. It is a species-typical behavior that is controlled by neural circuits in the brain.- In humans :...
. White Storks exhibit this behaviour exclusively at the nest site. Standing birds preen the heads of sitting birds, sometimes these are parents grooming juveniles, and sometimes juveniles preen each other. Unlike most storks, it never adopts a spread-winged posture, though it is known to droop its wings (holding them away from its body with the primary feathers pointing downwards) when its plumage is wet.
A White Stork's droppings, containing faeces and urine, are sometimes directed onto its own legs, making them appear white. The resulting evaporation provides cooling and is termed urohidrosis
Urohidrosis
Urohidrosis is the habit in some birds of defecating onto the scaly portions of the legs as a cooling mechanism, using evaporative cooling of the fluids. Several species of storks and New World vultures exhibit this behaviour. Birds' droppings consist of faeces and urine, which are excreted...
. Birds that have been ringed
Bird ringing
Bird ringing or bird banding is a technique used in the study of wild birds, by attaching a small, individually numbered, metal or plastic tag to their legs or wings, so that various aspects of the bird's life can be studied by the ability to re-find the same individual later...
can sometimes be affected by the accumulation of droppings around the ring leading to constriction and leg trauma. The White Stork has also been noted for tool use by squeezing moss in the beak to drip water into the mouths of their chicks.
Communication
The adult White Stork's main sound is noisy bill-clattering, which has been likened to distant machine gun fire. The bird makes these sounds by rapidly opening and closing its beak so that a knocking sound is made each time its beak closes. The clattering is amplified by its throat pouchGular skin
Gular skin , in ornithology, is an area of featherless skin on birds that joins the lower mandible of the beak to the bird's neck....
, which acts as a resonator
Resonator
A resonator is a device or system that exhibits resonance or resonant behavior, that is, it naturally oscillates at some frequencies, called its resonant frequencies, with greater amplitude than at others. The oscillations in a resonator can be either electromagnetic or mechanical...
. Used in a variety of social interactions, bill-clattering generally grows louder the longer it lasts, and takes on distinctive rhythms depending on the situation—for example, slower during copulation and briefer when given as an alarm call. The only vocal sound adult birds generate is a weak barely audible hiss; however, young birds can generate a harsh hiss, various cheeping sounds, and a cat-like mew they use to beg for food. Like the adults, young also clatter their beaks. The up-down display is used for a number of interactions with other members of the species. Here a stork quickly throws its head backwards so that its crown rests on its back before slowly bringing its head and neck forwards again, and this is repeated several times. The display is used as a greeting between birds, post coitus, and also as a threat display
Threat display
Threat display is a type of display behaviour aiming at intimidation of a potential enemy. It may be directed at a rival of the same species , or at a potential threat from a different species....
. Breeding pairs are territorial
Territory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
over the summer, and use this display, as well as crouching forward with the tails cocked and wings extended.
Feeding
White Storks consume a wide variety of animal prey. They prefer to forage in meadows that are within roughly 5 km (3 mi) of their nest and sites where the vegetation is shorter so that their prey is more accessible. Their diet varies according to season, locality and prey availability. Common food items include insects (primarily beetles, grasshoppers, locusts and crickets), earthworms, reptiles, amphibians, particularly frog species such as the edible frogEdible Frog
The Edible Frog is a name for a common European frog, also known as the common water frog or green frog . It is used for food, particularly in France for the delicacy frog legs...
(Pelophylax kl. esculentus) and common frog
Common Frog
The Common Frog, Rana temporaria also known as the European Common Frog or European Common Brown Frog is found throughout much of Europe as far north as well north of the Arctic Circle in Scandinavia and as far east as the Urals, except for most of Iberia, southern Italy, and the southern Balkans...
(Rana temporaria) and small mammals such as voles, moles, and shrews. Less commonly, they also eat bird eggs and young birds, fish, molluscs, crustaceans and scorpions. They hunt mainly during the day, swallowing small prey whole, but killing and breaking apart larger prey before swallowing. Birds returning to Latvia during spring have been shown to locate their prey, moor frogs (Rana arvalis), by homing in on the mating calls produced by aggregations of male frogs.
The diet of non-breeding birds is similar to that of breeding birds, but food items are more often taken from dry areas. White Storks wintering in western India have been observed to follow blackbuck
Blackbuck
Blackbuck is a species of antelope native to the Indian subcontinent. Their range decreased sharply during the 20th century. Since 2003, the IUCN lists the species as near threatened....
to capture insects disturbed by them. Wintering White Storks in India sometimes forage along with the Woolly-necked Stork
Woolly-necked Stork
The Woolly-necked Stork or White necked stork , Ciconia episcopus, is a large wading bird in the stork family Ciconiidae. It can also be known as the Espiscopos....
(Ciconia episcopus). Food piracy has been recorded in India with a rodent captured by a Western Marsh Harrier
Western Marsh Harrier
The Western Marsh-harrier is a mid-sized harrier, a bird of prey from temperate and subtropical western Eurasia and adjacent Africa. It is also known as the Eurasian Marsh-harrier....
appropriated by a White Stork, while Montagu's Harrier
Montagu's Harrier
The Montagu's Harrier is a migratory bird of prey of the harrier family. Its common name commemorates the British naturalist George Montagu.-Plumage:...
is known to harass White Storks foraging for voles in some parts of Poland.
Breeding and lifespan
The White Stork breeds in open farmland areas with access to marshy wetlands, building a large stick nestBird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
in trees, on buildings, or on purpose-built man-made platforms. Each nest is 1 – in depth, 0.8 – in diameter, and 60 – in weight. Nests are built in loose colonies. Not persecuted as it is viewed as a good omen, it often nests close to human habitation; in southern Europe, nests can be seen on churches and other buildings. The nest is typically used year after year especially by older males. The males arrive earlier in the season and choose the nests. Larger nests are associated with greater numbers of young successfully fledged, and appear to be sought after. Nest change is often related to a change in the pairing and failure to raise young the previous year, and younger birds are more likely to change nesting sites. A succession of pairs have been observed occupying a nest for a few days before moving on, the reason for which is unclear.
Several bird species often nest within the large nests of the White Stork. Regular occupants are House Sparrow
House Sparrow
The House Sparrow is a bird of the sparrow family Passeridae, found in most parts of the world. One of about 25 species in the genus Passer, the House Sparrow occurs naturally in most of Europe, the Mediterranean region, and much of Asia...
s, Tree Sparrow
Tree Sparrow
The Eurasian Tree Sparrow is a passerine bird in the sparrow family with a rich chestnut crown and nape, and a black patch on each pure white cheek. The sexes are similarly plumaged, and young birds are a duller version of the adult...
s, and Common Starlings; less common residents include Eurasian Kestrels, Little Owl
Little Owl
The Little Owl is a bird which is resident in much of the temperate and warmer parts of Europe, Asia east to Korea, and north Africa. It is not native to Great Britain, but was first introduced in 1842, and is now naturalised there...
s, European Roller
European Roller
The European Roller, Coracias garrulus, is the only member of the roller family of birds to breed in Europe. Its overall range extends into the Middle East and Central Asia and Morocco....
s, White Wagtail
White Wagtail
"Pied Wagtail" redirects here. For the related African bird, see African Pied Wagtail.The White Wagtail is a small passerine bird in the wagtail family Motacillidae, which also includes the pipits and longclaws. This species breeds in much of Europe and Asia and parts of north Africa...
s, Black Redstart
Black Redstart
The Black Redstart Phoenicurus ochruros is a small passerine bird in the redstart genus Phoenicurus. Like its relatives, it was formerly classed as a member of the Thrush family , but is now known to be an Old World flycatcher .-Description:The Black Redstart is 13–14.5 cm in length and 12–20...
s, Eurasian Jackdaws, and Spanish Sparrow
Spanish Sparrow
The Spanish Sparrow or Willow Sparrow is a passerine bird of the sparrow family Passeridae. It is found in the Mediterranean region and southwest and central Asia...
s. Paired birds greet by engaging in up-down and head-shaking crouch displays, and clattering the beak while throwing back the head. Pairs copulate frequently throughout the month before eggs are laid. High-frequency pair copulation is usually associated with sperm competition
Sperm competition
Sperm competition is a term used to refer to the competitive process between spermatozoa of two different males to fertilize an egg of a lone female. Competition occurs whenever females engage in promiscuous mating to increase their chances in producing more viable offspring...
and high frequency of extra-pair copulation; however, extra-pair copulation is infrequent in White Storks.
A White Stork pair raises a single brood a year. The female typically lays four eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
, though clutches
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
of 1–7 have been recorded. The eggs are white, but often look dirty or yellowish due to a glutinous covering. They measure 72.58 by 51.86 mm (2.9 by 2 in), and weigh 96 –, of which 10.76 g (0.379547832251005 oz) is shell. Incubation begins as soon as the first egg is laid, so the brood hatches asynchronously, beginning 33 to 34 days later. The first hatchling typically has a competitive edge over the others. While stronger chicks are not aggressive towards weaker siblings, as is the case in some species, weak or small chicks are sometimes killed by their parents. This behaviour occurs in times of food shortage to reduce brood size and hence increase the chance of survival of the remaining nestlings. White Stork nestlings do not attack each other, and their parents' method of feeding them (disgorging large amounts of food at once) means that stronger siblings cannot outcompete weaker ones for food directly, hence parental infanticide is an efficient way of reducing brood size. Despite this, this behaviour has not commonly been observed.
The temperature and weather around the time of hatching in spring is important; cool temperatures and wet weather increase chick mortality and reduce breeding success rates. Somewhat unexpectedly, studies have found that later-hatching chicks which successfully reach adulthood produce more chicks than do their earlier-hatching nestmates. The body weight of the chicks increases rapidly in the first few weeks and reaches a plateau of about 3.4 kg (7.5 lb) in 45 days. The length of the beak increases linearly for about 50 days. Young birds are fed with earthworms and insects, which are regurgitated by the parents onto the floor of the nest. Older chicks reach into the mouths of parents to obtain food. Chicks fledge 58 to 64 days after hatching.
White Storks generally begin breeding when about four years old, although the age of first breeding has been recorded as early as two years and as late as seven years. The oldest known wild White Stork lived for 39 years after being ringed
Bird ringing
Bird ringing or bird banding is a technique used in the study of wild birds, by attaching a small, individually numbered, metal or plastic tag to their legs or wings, so that various aspects of the bird's life can be studied by the ability to re-find the same individual later...
in Switzerland, while captive birds have lived for more than 35 years.
Parasites and diseases
White Stork nests are habitatHabitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s for an array of small arthropods, particularly over the warmer months after the birds arrive to breed. Nesting over successive years, the storks bring more material to line their nests and layers of organic material accumulate within them. Not only do their bodies tend to regulate temperatures within the nest, but excrement, food remains and feather and skin fragments provide nourishment for a large and diverse population of free-living mesostigmatic
Mesostigmata
Mesostigmata is an order of mites belonging to the Parasitiformes. Unlike most members of that group, many of these mites are not parasitic but free-living and predatory. They can be recognized by the single pair of spiracles positioned laterally on the body....
mites. A survey of twelve nests found 13,352 individuals of 34 species, the most common being Macrocheles merdarius, M. robustulus, Uroobovella pyriformis and Trichouropoda orbicularis, which together represented almost 85% of all the specimens collected. These feed on the eggs and larvae of insects and on nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
s, which are abundant in the nest litter. These mites are dispersed by coprophilous
Coprophagia
Coprophagia or coprophagy is the consumption of feces, from the Greek κόπρος copros and φαγεῖν phagein . Many animal species practice coprophagia as a matter of course; other species do not normally consume feces but may do so under unusual conditions...
beetles, often of the family Scarabaeidae
Scarabaeidae
The family Scarabaeidae as currently defined consists of over 30,000 species of beetles worldwide. The species in this large family are often called scarabs or scarab beetles. The classification of this family is fairly unstable, with numerous competing theories, and new proposals appearing quite...
, or on dung brought by the storks during nest construction. Parasitic mites do not occur, perhaps being controlled by the predatory species. The overall impact of the mite population is unclear, the mites may have a role in suppressing harmful organisms (and hence be beneficial), or they may themselves have an adverse effect on nestlings.
The birds themselves host species belonging to more than four genera of feather mites. These mites, including Freyana pelargica, Pterolichus ciconiae and Xoloptes didactylus live on fungi growing on the feathers. The fungi found on the plumage may feed on the keratin
Keratin
Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...
of the outer feathers or on feather oil. Chewing lice such as Colpocephalum zebra tend to be found on the wings, and Neophilopterus incompletus elsewhere on the body.
The White Stork also carries several types of internal parasites, including Toxoplasma gondii
Toxoplasma gondii
Toxoplasma gondii is a species of parasitic protozoa in the genus Toxoplasma. The definitive host of T. gondii is the cat, but the parasite can be carried by many warm-blooded animals . Toxoplasmosis, the disease of which T...
and intestinal parasite
Intestinal parasite
Intestinal parasites are parasites that populate the gastro-intestinal tract in humans and other animals. They can live throughout the body, but most prefer the intestinal wall. Means of exposure include: ingestion of undercooked meat, drinking infected water, and skin absorption...
s of the genus Giardia
Giardia
Giardia is a genus of anaerobic flagellated protozoan parasites of the phylum Metamonada in the supergroup "Excavata" that colonise and reproduce in the small intestines of several vertebrates, causing giardiasis, commonly known as Beaver fever...
. A study of 120 White Stork carcasses from Saxony-Anhalt
Saxony-Anhalt
Saxony-Anhalt is a landlocked state of Germany. Its capital is Magdeburg and it is surrounded by the German states of Lower Saxony, Brandenburg, Saxony, and Thuringia.Saxony-Anhalt covers an area of...
and Brandenburg
Brandenburg
Brandenburg is one of the sixteen federal-states of Germany. It lies in the east of the country and is one of the new federal states that were re-created in 1990 upon the reunification of the former West Germany and East Germany. The capital is Potsdam...
in Germany yielded eight species of trematode
Trematoda
Trematoda is a class within the phylum Platyhelminthes that contains two groups of parasitic flatworms, commonly referred to as "flukes".-Taxonomy and biodiversity:...
(fluke), four cestode
Cestoda
This article describes the flatworm. For the medical condition, see Tapeworm infection.Cestoda is the name given to a class of parasitic flatworms, commonly called tapeworms, of the phylum Platyhelminthes. Its members live in the digestive tract of vertebrates as adults, and often in the bodies...
(tapeworm) species, and at least three species of nematode. One species of fluke, Chaunocephalus ferox, caused lesions in the wall of the small intestine in a number of birds admitted to two rehabilitation centers in central Spain, and was associated with reduced weight. It is a recognised pathogen and cause of morbidity in the Asian Openbill (Anastomus oscitans).
West Nile virus
West Nile virus
West Nile virus is a virus of the family Flaviviridae. Part of the Japanese encephalitis antigenic complex of viruses, it is found in both tropical and temperate regions. It mainly infects birds, but is known to infect humans, horses, dogs, cats, bats, chipmunks, skunks, squirrels, domestic...
(WNV) is mainly a bird infection that is transmitted between birds by mosquito
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
s. Migrating birds appear to be important in spread of the virus, the ecology of which remains poorly known. On 26 August 1998, a flock of about 1,200 migrating White Storks that had been blown off course on their southward journey landed in Eilat, in southern Israel. The flock was stressed as it had resorted to flapping flight to return to its migratory route, and a number of birds died. A virulent strain of West Nile virus was isolated from the brains of eleven dead juveniles. Other White Storks subsequently tested in Israel have shown anti-WNV antibodies
Antibody
An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...
. In 2008 three juvenile White Storks from a Polish wildlife refuge yielded seropositive
Serostatus
Serostatus is a term used to refer to the presence or absence of specific substances in the blood serum. Most commonly, this medical test is looking for specific antibodies in an effort to diagnose a particular disease....
results indicating exposure to the virus, but the context or existence of the virus in that country is unclear.
Conservation
The White Stork's decline due to industrialisationIndustrialisation
Industrialization is the process of social and economic change that transforms a human group from an agrarian society into an industrial one...
and agricultural changes (principally the draining of wetlands and conversion of meadows to crops such as maize
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...
) began in the 19th century: the last wild individual in Belgium was seen in 1895, in Sweden in 1955, in Switzerland in 1950 and in Holland in 1991. However, the species has since been reintroduced to many regions. It has been rated as Least Concern by the IUCN since 1994, after being evaluated as Near Threatened
Near Threatened
Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status...
in 1988. The White Stork is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA
AEWA
The Agreement on the Conservation of African-Eurasian Migratory Waterbirds is the largest of its kind developed so far under the Bonn Convention. It was concluded on 16 June 1995 at The Hague, the Netherlands and entered into force on 1 November 1999 after the required number of at least fourteen...
) applies. Parties to the Agreement are required to engage in a wide range of conservation strategies described in a detailed action plan. The plan is intended to address key issues such as species and habitat conservation, management of human activities, research, education, and implementation. Threats include the continued loss of wetlands, collisions with overhead power lines, use of persistent pesticides
Persistent organic pollutant
thumb|right|275px|State parties to the Stockholm Convention on Persistent Organic PollutantsPersistent organic pollutants are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes...
(such as DDT
DDT
DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....
) to combat locust
Desert locust
Plagues of the desert locust have threatened agricultural production in Africa, the Middle East, and Asia for centuries. The livelihood of at least one-tenth of the world’s human population can be affected by this voracious insect...
s in Africa, and largely illegal hunting on migration routes and wintering grounds.
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...
, 10,000 pairs in Lithuania (the highest known density of this species in the world), and 8,500 pairs in Latvia. In Estonia the population has also been increasing, numbering about 4,000 pairs in 2004. There were around 5,000 pairs in Romania and an estimated 4,818 breeding pairs in Bulgaria. In Germany, 3,000 of the total 3,400 pairs are in the former East Germany. Apart from Spain and Portugal (33,217 pairs and 7,684 pairs in 2004/05 respectively), populations in western Europe are generally much less stable; for instance, the once sizable Danish population declined to just three pairs in 2005.
In the 1980s, the population had fallen to fewer than nine pairs in the entire upper Rhine River valley, an area closely identified with the White Stork for centuries. Conservation efforts successfully increased the population of birds there to 270 pairs, largely due to the actions of the Association for the Protection and Reintroduction of Storks in Alsace
Alsace
Alsace is the fifth-smallest of the 27 regions of France in land area , and the smallest in metropolitan France. It is also the seventh-most densely populated region in France and third most densely populated region in metropolitan France, with ca. 220 inhabitants per km²...
and Lorraine
Lorraine (région)
Lorraine is one of the 27 régions of France. The administrative region has two cities of equal importance, Metz and Nancy. Metz is considered to be the official capital since that is where the regional parliament is situated...
. The reintroduction of zoo
Zoo
A zoological garden, zoological park, menagerie, or zoo is a facility in which animals are confined within enclosures, displayed to the public, and in which they may also be bred....
-reared birds has halted further declines in Italy (30 pairs), the Netherlands (9–12 pairs), and Switzerland (120–160 pairs). There were 601 pairs breeding in Armenia and around 700 pairs in the Netherlands in 2008, and few pairs also breed in South Africa, typically recent colonists from within the normal wintering population. In Poland, electric poles have been modified with a platform at the top to prevent the White Stork's large nest from disrupting the electricity supply, and sometimes nests are moved from an electric pole to a man-made platform. Introductions of zoo-reared birds in the Netherlands has been followed up by feeding and nest-building programs by volunteers. Similar reintroduction programs are taking place in Sweden, and Switzerland, where 175 pairs were recorded breeding in 2000. Long term viability of the population in Switzerland is unclear as breeding success rates are low, and supplementary feeding does not appear to be of benefit.
Cultural associations
Due to its large size, predation on vermin, and nesting behaviour close to human settlements and on rooftops, the White Stork has an imposing presence that has had an impact on human culture and folklore. In Ancient EgyptAncient Egypt
Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...
, it was associated with, and was the hieroglyph for, the Ba, or "soul". The Hebrew word for the White Stork is chasidah (חסידה), meaning "merciful" or "kind". Greek
Greek mythology
Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...
and Roman mythology
Roman mythology
Roman mythology is the body of traditional stories pertaining to ancient Rome's legendary origins and religious system, as represented in the literature and visual arts of the Romans...
portray storks as models of parental devotion, and it was believed that they did not die of old age, but flew to islands and took the appearance of humans. The bird is featured in two of Aesop's Fables
Aesop's Fables
Aesop's Fables or the Aesopica are a collection of fables credited to Aesop, a slave and story-teller believed to have lived in ancient Greece between 620 and 560 BCE. The fables remain a popular choice for moral education of children today...
: The Fox and the Stork and The Farmer and the Stork
The Farmer and the Stork
The Farmer and the Stork is one of Aesop's fables and is numbered 194 in the Perry Index. It appears in Greek in the collections of both Babrius and Aphthonius and has differed little in the telling over the centuries. The story relates how a farmer plants traps in his field to catch the cranes and...
. They were also thought to care for their aged parents, feeding them and even transporting them, and children's books depicted them as a model of filial values. A Greek law called Pelargonia, from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
word pelargos for stork, required citizens to take care of their aged parents. The Greeks also held that killing a stork could be punished with death. It was allegedly protected in Ancient Thessaly
Ancient Thessaly
Ancient Thessaly or Thessalia was one of the traditional regions of Ancient Greece. During the Mycenaean period, Thessaly was known as Aeolia, a name which continued to be used for one of the major tribes of Greece, the Aeolians, and their dialect of Greek, .-History:Thessaly was home to an...
as it hunted snakes, and widely held to be Virgil
Virgil
Publius Vergilius Maro, usually called Virgil or Vergil in English , was an ancient Roman poet of the Augustan period. He is known for three major works of Latin literature, the Eclogues , the Georgics, and the epic Aeneid...
's "white bird". Roman writers noted the White Stork's arrival in spring, which alerted farmers to plant their vines.
Followers of Islam
Islam
Islam . The most common are and . : Arabic pronunciation varies regionally. The first vowel ranges from ~~. The second vowel ranges from ~~~...
revered storks because they made an annual pilgrimage to Mecca
Mecca
Mecca is a city in the Hijaz and the capital of Makkah province in Saudi Arabia. The city is located inland from Jeddah in a narrow valley at a height of above sea level...
on their migration. Some of the earliest understanding on bird migration were initiated by an interest in White Storks; Pfeilstorch
Pfeilstorch
The term Pfeilstorch is given to storks injured by an arrow while wintering in Africa, before returning to Europe with the arrow stuck in their bodies. To date, around 25 Pfeilstörche have been documented....
("arrow storks") were found in Europe with African arrow
Arrow
An arrow is a shafted projectile that is shot with a bow. It predates recorded history and is common to most cultures.An arrow usually consists of a shaft with an arrowhead attached to the front end, with fletchings and a nock at the other.- History:...
s embedded in their bodies. A well-known example of such a stork found in the summer of 1822 in the German town of Klütz
Klütz
Klütz is a town in the Nordwestmecklenburg district, in Mecklenburg-Western Pomerania, Germany. It is situated near the Baltic Sea coast, 22 km northwest of Wismar, and 33 km northeast of Lübeck.-External links:...
in Mecklenburg
Mecklenburg
Mecklenburg is a historical region in northern Germany comprising the western and larger part of the federal-state Mecklenburg-Vorpommern...
was made into a mounted taxidermy specimen, complete with the ornate African arrow, that is now in the University of Rostock
University of Rostock
The University of Rostock is the university of the city Rostock, in the German state of Mecklenburg-Vorpommern.Founded in 1419, it is the oldest and largest university in continental northern Europe and the Baltic Sea area...
.
Storks have little fear of humans if not disturbed, and often nest on buildings in Europe. In Germany, the presence of a nest on a house was believed to protect against fires. They were also protected because of the belief that their souls were human. German and Dutch households would encourage storks to nest on houses, sometimes by constructing purpose-built high platforms, to bring good luck. Poles, Lithuanians and Ukrainians believe that storks bring harmony to a family on whose property they nest.
The White Stork is a popular motif on postage stamp
Postage stamp
A postage stamp is a small piece of paper that is purchased and displayed on an item of mail as evidence of payment of postage. Typically, stamps are made from special paper, with a national designation and denomination on the face, and a gum adhesive on the reverse side...
s, and it is featured on more than 120 stamps issued by more than 60 stamp-issuing entities. It is the national bird of Lithuania, and it was a Polish mascot at the Expo 2000
Expo 2000
Expo 2000 was a World's Fair held in Hanover, Germany from Thursday, June 1 to Tuesday, October 31, 2000. It was located on the Hanover fairground , which is famous for hosting CeBIT...
Fair in Hanover. In the 19th century, storks were also thought to only live in countries having a republican form of government. Polish poet Cyprian Kamil Norwid mentioned storks in his poem Moja piosnka (II) ("My Song (II)"):
Storks and childbirth
According to northern European legend, the stork is responsible for bringing babies to new parents. The legend is very ancient, but was popularised by a 19th century Hans Christian AndersenHans Christian Andersen
Hans Christian Andersen was a Danish author, fairy tale writer, and poet noted for his children's stories. These include "The Steadfast Tin Soldier," "The Snow Queen," "The Little Mermaid," "Thumbelina," "The Little Match Girl," and "The Ugly Duckling."...
story called The Storks. German folklore held that storks found babies in caves or marshes and brought them to households in a basket on their backs or held in their beaks. These caves contained adebarsteine or "stork stones". The babies would then be given to the mother or dropped down the chimney. Households would notify when they wanted children by placing sweets for the stork on the window sill. From there the folklore has spread around the world to countries such as the Philippines and South America.
In Slavic mythology and religion
Slavic mythology
Slavic mythology is the mythological aspect of the polytheistic religion that was practised by the Slavs before Christianisation.The religion possesses many common traits with other religions descended from the Proto-Indo-European religion....
, storks were thought to carry unborn souls from Iriy
Iriy
Iriy or Irij, according to neo-paganist manuals, was the paradise in old Slavic religion and part of Svarga. This term is probably derived from in contemporary Slavic languages....
to Earth in spring and summer. This belief still persists in the modern folk culture of many Slavic countries, in the simplified child story that "storks bring children into the world". Storks were seen by the Slavs as bringing luck, and killing one would bring misfortune. A long-term study that showed a spurious correlation between the numbers of stork nests and human births is widely used in the teaching of basic statistics
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
as an example to highlight that correlation does not necessarily indicate causation
Causality
Causality is the relationship between an event and a second event , where the second event is understood as a consequence of the first....
. The child-bringing myth has appeared in different forms in history. Children of African American
African American
African Americans are citizens or residents of the United States who have at least partial ancestry from any of the native populations of Sub-Saharan Africa and are the direct descendants of enslaved Africans within the boundaries of the present United States...
slaves were sometimes told that white babies were brought by storks, while black babies were born from buzzard eggs.
Psychoanalyst Marvin Margolis suggests the enduring nature of the stork fable of the newborn is linked to its addressing a psychological need, in that it allays the discomfort of discussing sex and procreation with children. Birds have long been associated with the maternal symbols from pagan goddesses such as Juno
Juno (mythology)
Juno is an ancient Roman goddess, the protector and special counselor of the state. She is a daughter of Saturn and sister of the chief god Jupiter and the mother of Mars and Vulcan. Juno also looked after the women of Rome. Her Greek equivalent is Hera...
to the Holy Ghost
Holy Spirit
Holy Spirit is a term introduced in English translations of the Hebrew Bible, but understood differently in the main Abrahamic religions.While the general concept of a "Spirit" that permeates the cosmos has been used in various religions Holy Spirit is a term introduced in English translations of...
, and the stork may have been chosen for its white plumage (depicting purity), size (in that it is big enough to carry an infant), and flight at high altitude (likened to flying between Earth and Heaven). The fable and its relation to the internal world of the child have been discussed by Sigmund Freud
Sigmund Freud
Sigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
, and Carl Jung
Carl Jung
Carl Gustav Jung was a Swiss psychiatrist and the founder of Analytical Psychology. Jung is considered the first modern psychiatrist to view the human psyche as "by nature religious" and make it the focus of exploration. Jung is one of the best known researchers in the field of dream analysis and...
. In fact, Jung recalled being told the story himself upon the birth of his own sister. The traditional link with the newborn continues with their use in advertising
Advertising
Advertising is a form of communication used to persuade an audience to take some action with respect to products, ideas, or services. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common...
for such products as nappies
Diaper
A nappy or a diaper is a kind of pant that allows one to defecate or urinate on oneself discreetly. When diapers become soiled, they require changing; this process is often performed by a second person such as a parent or caregiver...
and birth announcements
Baby announcement
A baby announcement or birth announcement is a notice traditionally sent to friends and family by the parents of a baby within the first year of the baby's birth for the primary purpose of alerting friends and family to the birth of the baby...
.
There were negative aspects to stork folklore as well; a Polish folk tale relates how God made the stork's plumage white, while the Devil gave it black wings, imbuing it with both good and evil impulses. They were also associated with handicapped or stillborn babies in Germany, explained as the stork having dropped the baby en route to the household, or as revenge or punishment for past wrongdoing. A mother who was confined to bed around the time of childbirth was said to have been "bitten" by the stork. In Denmark, storks were said to toss a nestling off the nest and then an egg in successive years. In medieval England, storks were also associated with adultery, possibly inspired by their courtship rituals. Their preening and posture saw them linked with the attribute of self-conceit.
External links
- White Stork sounds on the xeno-canto.org website
- White Stork videos, photos and sounds on the Handbook of Birds of the World's Internet Bird Collection website