During the spring, male birds take over a territory that they will use for nesting. When a male bird has attracted a female bird to its territory by singing, the two birds will build a nest and reproduce. 

The female bird lays eggs and broods over them in their nest for a couple of weeks. The number of eggs laid varies between different species. For example, the pied flycatcher often lays six eggs, but the blue tit can sometimes lay even 13!

After the brooding period, the young birds hatch from their eggs. At first, the young birds are blind and have no feathers. They continue to grow and develop in the nest. Small birds feed their offspring by bringing them insects and spiders.

When the offspring have grown in the nest for 2–3 weeks, they are ready to leave their nest.