Body length: 17-22 cm
Body mass: 16-24 g
Appearance: glossy, very dark-blue back contrasting with white underparts. Red throat-patch gives way to black bib below. Forked tail with elongated streamers longer in males than females.
Remains common, and in places (like farming villages) very common. Females choose males with long, symmetrical tail-streamers, though these actually reduce flight efficiency. Pairs build mud-nests together, mostly in farm buildings, house eaves or under bridges. Nests are lined with feathers and soft plant matter, and may be returned to year after year. Swallows eat insects caught in flight, often resting on wires between times, and only rarely perching on the ground. Birds famously make long-distance migratory flights to African wintering grounds.
Descriptions drawing on content of Ptaki Polski (“Birds of Poland”) - a book authored by Andrzej G. Kruszewicz, and published by MULTICO Oficyna Wydawnicza Sp. z o.o.