Why Do Storks Nest on Roofs and Chimneys? Stork Nests

What storks look for in a nest site

The white stork is a large, broad-winged bird that weighs 2.3–4.5 kg (5.1–9.9 lb) and has a wingspan of up to about 2.15 m (7 ft). A good nest site has to meet several needs at once:

• Height. A high site keeps eggs and chicks away from foxes, martens and other ground predators.
• Open approach. Storks are not agile fliers. They need a clear path to glide in and land, and room to take off without crashing into branches.
• A broad, strong base. Stork nests become enormous and very heavy, so they need a solid foundation such as a chimney top, ridge, tower or thick fork in a tree.
• Food nearby. Storks usually feed within a few kilometers of the nest, often 5 km (3 mi) or less, in wet meadows, pastures and marshes.
• A wide view. From a high perch, storks can watch for rivals and danger in every direction.

Roofs, chimneys, church towers and water towers in farming villages tick every box. The village is usually surrounded by exactly the open, damp grassland where storks find frogs, earthworms and insects.

Why buildings replaced trees

Long ago, white storks nested mainly in big trees and on rocks. In the Middle Ages, as forests in Europe were cleared for fields and pastures, storks spread into the new open farmland. The tall buildings of villages and towns offered secure nest sites in landscapes with few big trees left.

People also welcomed them. Because storks were seen as lucky, they were rarely disturbed. Over centuries, a strong link developed between storks and human settlements. Today, most white storks in central and western Europe nest on structures built by people, though many in eastern Europe and Iberia still use trees.

Electricity poles are now very popular, especially in Poland and Spain. They are tall, open and often stand in the middle of farmland. Unfortunately, nests on live power lines can cause short circuits, and storks can be electrocuted. Power companies in several countries now fit special platforms on top of poles to keep the nest safely above the wires.

How big are stork nests?

White stork nests are built from sticks and branches and lined with grass, moss, earth, rags and sometimes paper or plastic. Both partners build, and they add new material every year. Over time, a nest can become huge:

Some nests in Europe have been used for decades, and a few famous nests are said to have been occupied for well over a century. Large old nests are prized: studies show that pairs in bigger nests often raise more chicks. The male usually arrives first in spring and reclaims the nest before the female returns.

These nests are busy places. House sparrows, tree sparrows and starlings often build their own nests in the sides of a stork nest, and kestrels, little owls and jackdaws have been found nesting there too. It is a small apartment block on a chimney.

Why villages welcome storks

Across much of Europe, having a stork nest on your house has long been a matter of pride. Traditional beliefs include:

• Good luck and harmony. In central and eastern Europe, storks were thought to bring happiness to the family below.
• Protection from fire. In parts of Germany, a stork nest was believed to protect the house from fire and lightning.
• New babies. The famous legend that storks bring babies is told in Do storks deliver babies?

To attract storks, people in Germany, the Netherlands and Poland traditionally placed old cartwheels or wooden frames on roofs as nest bases. Some towns are now famous for their storks. In Rust, in the Burgenland region of Austria, storks nest on many old town chimneys. In Alsace, France, the stork is a regional emblem, and towns such as Strasbourg and Colmar have helped the birds return. In Spain, cities such as Alcalá de Henares have dozens of nests on churches and monasteries, and in the Polish village of Żywkowo, stork nests on farm buildings draw thousands of visitors a year.

Nest platforms and stork conservation

Providing safe nest sites has been an important part of the white stork’s comeback in Europe. Conservation groups and local volunteers:

• Build platforms on poles, roofs and towers, sometimes with a starter nest of sticks.
• Move nests from dangerous power poles onto purpose-built supports nearby.
• Reinforce old roofs and chimneys so nests can stay safely.

Platforms alone are not enough: storks also need wet meadows and pastures full of food. When farmland is drained or turned into large crop fields, storks may abandon nests even on the best rooftops. That is why stork protection also means restoring wetlands.

White storks are protected under EU law, and active nests may not be destroyed. If a nest causes a problem, wildlife authorities can advise on moving it outside the breeding season. To see where the owners of these rooftop nests go in winter, read Where do storks migrate?