Every fourth stork in the world comes from Poland. There is no other country which can boast nesting of so many birds of this species. It is estimated that recently there have been around 40 900 pairs of storks nesting on the Polish territory. However, their habitat is not evenly distributed due to various factors such as human activity: development of agriculture and industry, destroying wetlands; existence of forest complexes and unpolluted environment. The biggest density of stork nests is observed in the North- Eastern and Eastern part of Poland. The average density for Poland is 13,1 of pairs per 100 square kilometers.
Storks rebuild their nests each year. The key role is played by the male, which brings all building material, and female is arranging it properly. The basis of construction material consists of sticks and branches and inner part of a nest is lined with earth, hay, bits of paper, rugs and sometimes nylon ropes which can present a significant threat to nestlings. The nest, seen from above, has an oval or elliptic shape with up to 200 cm in diameter and is constructed above the ground, on poles, very often in close proximity of human settlements: on the tops of barns and houses.
Storks begin to lay eggs in the second part of April. The female broods the eggs for 33-34 days. The first nestlings hatch around the 20th of May and they usually leave a nest at the end of July. Storks are carnivores, they eat small invertebrates and tiny mammals as well. They also hunt for rodents, moles, nestling of other bird species, fish and other amphibians. The structure of food depends mainly on spatial and periodical diversity of a specific food type.
Storks leave Poland at the end of August. Before they set off for Africa, they gather at so called gaggles, that is huge flocks consisting of tens and hundreds of birds, which prey and rest together. The spectacular gaggles bring attention of observers because they announce the end of summer.
Storks have been present in the Polish folk culture for centuries. There are a lot of superstitions and beliefs which are strictly connected with the birds and the role they play in our lives. Among the most common ones there is of course the superstition about storks bringing babies. Constructing of stork nest in a particular household is believed to bring its owner good luck and prosperity. It is also believed to protect a house from thunder strikes. Storks are also appreciated for their role as beneficial animals: they feed on species considered to be pests, such as rodents. There is also a belief the stork couples stick together all their lives as well as very often people would say that the same couple visits them every year. The latter is possible to verify only provided the birds have been marked with rings. The birds tend to divide the nests into better or worse situated rather than into our and strange. In case storks came back to their own nest every year, no frequent fights would occur. People also think that frogs constitute main food of the birds. Stork is a carnivore and thus it preys practically for every animal it is able to swallow.
Storks, being constantly present in Polish landscape, remain its vivid symbol and have found their place in our folktales, proverbial sayings, superstitions thus entering Polish culture as its inseparable symbol.