The young bird was naked and blind when born, but grew and developed rapidly. When feathered it was similar in color to that of the adult female, but its feathers were tipped with white, giving it a scaled appearance. It remained in the nest about fourteen days, being fed and cared for by the parent birds. By this time it had grown large and plump and usually weighed more than either of its parents. It had developed enough to take care of itself and soon fluttered to the ground to hunt for its food.
Authorities differ as to how many times the passenger pigeon nested in a season.
The general opinion was that the birds normally nested twice in a season, but this can neither be proved nor disproved since no accurate records of nestings were made. During the late summer the flocks of passenger pigeons frequently moved about at random in the northern forests in search of food, but as fall approached and temperature changes became sharp the flocks of passenger pigeons began their migration to the southern wintering areas. Because the passenger pigeon congregated in such huge numbers, it needed large forests for its existence. When the early settlers cleared the eastern forests for farmland, the birds were forced to shift their nesting and roosting sites to the forests that still remained. As their forest food supply decreased, the birds began utilizing the grain fields of the farmers.