Female age and egg size in the Lesser Snow Goose

younger birds laying slightly smaller eggs in each position within the laying sequence. Some physiological maturation process was probably responsible for the smaller eggs younger birds laid because the pattern held within individuals. However, changes in egg size and shape may be due to breeding experience rather than age itself. We detected no evidence for age-specific differences in egg size of older birds. Thus, neither senescent declines in egg size nor an increased allocation of reserves to reproduction appear to be occurring in this species.