Most bird species have only one breeding season in the year. For many birds, the breeding season begins with the males singing their characteristic songs at frequent intervals.
Many males also go through courting rituals to attract females.
These sights and sounds reinforce bonding between a pair of birds and promote mating activity. Many small male land birds defend a territory, which will be used by the pair when they rear their young. Some sea birds that nest on rocky ledges on cliffs, defend a very small territory. When a female is attracted to the male, the pair constructs a nest, mate and the female lays her eggs in the nest. Among the most spectacular courtship displays are those of the birds of paradise and some pheasant species.