Acta Zoologica Cracoviensia, 15() 1970
Biology of the Woodlark Lullula arborea (Linnaeus, 1758) (Aves) in the Rzepin Forest (Western Poland)
Abstract:
In the Rzepin region the arrival of Woodlarks falls at the end of February and in the first half of March. They take possession chiefly of young pine plantations as their territories and the situation of their nests is to a great extent connected with the distance of the adjacent timber forest. They, as a rule, nest once a year, mostly in May and June. The nest is constructed by the female alone. It lays 2-6 (on the average 3∙97) eggs. The average measurements of eggs are 20∙63 x 15∙77 mm. Fourteen-day egg incubation is performed by the female only. After the hatching of the young the egg-shells are eaten by the parents and so is the greater part of the faeces of the young. Nestlings are fed by both the male and female. They leave the nest between the 10th and 13th day of life; next they keep to small family flocks. The birds depart from the region at mid-October. Their main food constituent consists of insects (larvae and imagines), among them a large number of forest vermin; these are followed by spiders and seeds (chiefly those of pine and grasses). Losses of eggs and nestlings are remarkable. The mean number of fledglings leaving the nest is 1-85.
