One of the three Swallows that comes to Poland is House Martin (Delichon urbicum). It builds its nests outside buildings, mainly near windows. House Martin spends many hours in flight, hovering quite high. It breeds from one to three broods a year. The birds stay in the nest until the end of September at the latest, and then they fly away to the wintering grounds. The House Martin walks clumsily on the ground, mainly to collect mud for building a nest. Building its nest of mud and dry twigs on the walls of buildings, maneuvering its body like an agile acrobat. It also helps itself with its tail and sharp claws. It happens, unfortunately, that building owners drop almost ready nests, and sometimes, even worse, with young swallows or eggs. We appeal to: building administrators, owners of houses and apartments - do not remove martin nests! this is prohibited by law. House Martins are very necessary because they feed on flies, mosquitoes and other hostile insects. Once the house martin has built a nest, it cannot be removed. You can only protect this place from dirt by installing a shelf under the nest that collects droppings. It is always worth having a martin in your neighborhood, because it eats insects, especially those annoying to humans and animals. If we do not allow Swallows to breed, insects will become a nuisance and unpleasant for us. We are not alone, there are birds among us, which are our allies in the fight against hostile insects. Let them live and raise their young - then we will live better.