Incubation and Fledging Periods of African Birds

Abstract

Difficulties and necessary precautions in recording fledging and incubation periods are reviewed. Data are given, mostly for the first time, for about forty-five Tropical African species, some with many replications. None of the birds have incubation periods shorter than those of comparable Temperate Zone birds and some have slightly longer. As with Temperate Zone birds there is a tendency for fledging and incubation periods to be more or less equal in the same species, but hole-dwelling and long-winged birds take longer to fledge than to hatch. On the whole the African birds take longer to fledge than do comparable Temperate Zone birds, but not in (inverse) proportion to the shorter daylight. Temperature, at least within the seasonal variation at Amani (ca. 4° C.), does not affect length of individual incubation or fledging period.