In the Gruinae species, incubation begins after the first egg is laid. Wattled Cranes, at 33-36 days, have the longest incubation period. Cranes of the northern latitudes, including the Whooping and Siberian Cranes, experience such short growing seasons that even if they did produce second clutches, it would be difficult to fledge the young in time to undertake migration. In captivity, however, females of these and other species have been induced to lay repeatedly through the removal of the eggs, either one at a time or as clutches. In this manner, females have regularly produced up to ten or more eggs in a single breeding season.
Adults care for their chicks continuously through the pre-fledging period.
In general, chicks of these species fledge at between 50 and 90 days. On average, the Demoiselle Crane has the shortest fledging period, usually between 55 and 60 days. Chicks of these species usually fledge at between 85 and 100 or more days. The Wattled Crane has the longest fledging period at about 90-130 days. The productivity of a given crane population can be measured in several ways, but is most easily determined by counting the number of juveniles in the flocks during the non-breeding period.