Stork

White storks breed across a broad arc of territory stretching from Portugal and Morocco in the west through Central Europe, the Middle East, and into Central Asia. They are strongly tied to open landscapes: river floodplains, wet meadows, shallow marshes, and farmland where the grass is kept short by grazing animals. Villages and small towns suit them well, since rooftops and electricity poles offer elevated nest sites with easy access to foraging ground nearby. After breeding, the entire population heads south to spend the northern winter in Africa south of the Sahara, with the largest concentrations gathering in the Sahel zone, East Africa, and South Africa. Birds from western Europe generally winter in West Africa, while those breeding further east tend to travel to East and southern Africa. A separate subspecies, the Turkestan white stork, breeds in Central Asia and spends the winter from Iran to India.

Few European birds eat as wide a variety of prey as the white stork. Frogs and toads are a staple during the breeding season, but earthworms, large insects, fish, snakes, lizards, and small mammals are all taken whenever available. Storks forage mainly by walking slowly through short vegetation or shallow water, striking at prey with a sudden thrust of the bill. Agricultural fields are important feeding sites, particularly after plowing, when invertebrates are exposed at the surface. In their African wintering areas, locusts and other swarming insects can make up a huge part of the diet. The birds are opportunistic and will readily shift to whatever food source is most abundant at any given time, which is one reason they cope well across such a wide range of habitats.

The nest of a white stork is one of the most impressive structures built by any European bird. Pairs construct a wide platform of sticks, lining the cup with grass, moss, and other soft material. Rooftops, church towers, chimneys, and large trees are all used, and in many parts of Spain and Portugal, purpose built nest platforms are erected on poles to encourage the birds. What makes stork nests truly remarkable is their longevity: the same nest is reused year after year, with fresh material added each spring. Over time, a nest can grow to two meters across and become a small ecosystem of its own, with sparrows and starlings nesting in its walls. The female usually lays four eggs, and both parents share incubation for 33 to 34 days. The chicks fly 58 to 64 days after hatching, and during that time adult storks are almost silent: instead of calling, they greet each other by throwing the head back and clattering the bill loudly.

Every autumn, white storks undertake one of the most spectacular migrations of any bird in the world. Because they rely on rising columns of warm air called thermals to gain altitude and glide forward without flapping, they cannot cross large stretches of open water where thermals do not form. This forces the entire European population to funnel through two narrow land bridges: the Strait of Gibraltar in the west and the Bosphorus in the east. At these bottlenecks, hundreds of thousands of birds can be seen passing on a single day during peak movement. On the eastern route alone, about 530,000 white storks pass through the Middle East each year, which makes them one of the most common migrants over Israel. The journey to southern Africa covers up to 20,000 kilometers in a round trip, and the trip north in spring usually takes longer than the trip south. It was a white stork that helped prove bird migration: in 1822 a stork shot in Germany was found with an African spear through its neck, the famous Pfeilstorch, or arrow stork. Birds typically depart their breeding grounds in late summer and return the following spring, with experienced adults often arriving back at their nests before younger birds.

This page is about the white stork, the best known of about twenty species of storks around the world, but several of its relatives are just as famous. The black stork (Ciconia nigra) is its closest cousin in Europe: glossy black with a white belly and red bill, it is shy and nests deep in old forests instead of on rooftops. The marabou stork (Leptoptilos crumenifer) of Africa is the giant of the family, a bald headed scavenger with a pink throat pouch and one of the largest wingspans of any land bird, often seen at carcasses and rubbish dumps alongside vultures. In the Americas, the wood stork (Mycteria americana) is the only stork that breeds in the United States, found in the swamps of Florida and the southeast, with a bare grey head and a heavy curved bill. And then there is the shoebill, often called the shoebill stork or whale headed stork, with its huge shoe shaped bill. Despite the name, it is not a true stork: it belongs to its own family, Balaenicipitidae, and its closest relatives are the pelicans. It lives in the papyrus swamps of East and Central Africa and is listed as Vulnerable.

Across much of western Europe, white stork numbers collapsed during the twentieth century. Drainage of wetlands, the heavy use of pesticides on farmland, power lines, and hunting along migration routes all took a serious toll. In countries such as Sweden and Switzerland, the species disappeared entirely as a breeding bird. Recovery began early in some places: Switzerland started its reintroduction at Altreu in 1948, and from the 1980s onward programs in many countries restored wetlands, installed safe nest platforms, and released captive bred birds. The last international census, in 2004 and 2005, counted 52,500 pairs in Poland, 33,217 in Spain, 30,000 in Ukraine, 20,000 in Belarus, 13,000 in Lithuania, and more than 10,000 each in Latvia and Russia, and in 2020 the species bred in Britain for the first time in over 600 years. The IUCN lists it as Least Concern. Collisions with power lines, changes in farming, and conditions in the African wintering grounds still affect how well populations do each year.