Passage: Wood thrushes are monogamous. Breeding pairs form in mid-April to early-May, and usually last throughout the breeding season. Most thrushes find a new mate each year, and mate guarding and extra-pair copulations have not been observed in this species.Some male wood thrushes arrive at the breeding grounds several days before the earliest females while other males arrive at the same time as the females, establishing territories ranging in size from 0.08 to 0.8 hectares (one-fifth of an acre to two acres). The female typically leads silent circular flights 1–1.8 m (3.3–5.9 ft) from the ground, with the male chasing. Six or more flights generally take place in succession. The pairs will perch together and feed each other in between flights. The male begins to sing at dawn and dusk a few days after arriving at breeding grounds. Early in the breeding season, the male sings from high perches in the tallest trees, but as the season progresses, it sings somewhat shorter and less elaborate songs from lower perches. Each day's singing begins and is most intense just before sunrise. The male may sing throughout the day but especially at dusk. The song season is usually over by the end of July.Typically, the female chooses the nest site and builds the nest. However, there has been some indication that the male is able to influence the selection of the nest site by perching nearby and singing. Usually, though, the female chooses whether or not to accept or reject the nest site suggested by the male. The nest is usually sited in a dense patch of vegetation in a tree or shrub that provides concealment and shade. It is usually made of dead grasses, stems, and leaves, and lined with mud, and placed in a fork at a horizontal branch. The nest is not reused. Usually, two broods are attempted, although three to four separate nests may be built before a pair succeeds. Two to four pale blue eggs are laid at the rate of one per day. The eggs are incubated by the female only for 11 to 14 days, with the average being 13 days. Like all...

Question: How long are eggs kept in incubation?
11 to 14 days