Northern Prairie Wildlife Research Center
|Year||N||Median initiation datea||Temperature (C)||90% quantile||10% quantile||Season length|
We were unable to detect a difference in median nest initiation date between SY and ASY nesters (Table 4). Coulter and Miller (1968) and Dzubin and Gollop (1972) suggested that older hens nest earlier than young hens. Older birds may nest earlier than young hens; however, our sample of nests was not sufficient to demonstrate the difference. Batt and Prince (1979) demonstrated that there is considerable genetic variation among females in the date of first nesting in penned birds. This variation undoubtedly adds to the difficulty of demonstrating age-related differences in nest initiation date. Batt and Prince (1978) also failed to demonstrate a difference in nest initiation between ages, but their captive birds were fed ad libitum and the hens did not have to compete for resources.
|N||Julian day||N||Julian day|
hens in first year of nesting.
bAfter-second-year hens in their second or later nesting years.