Diagram showing the different ages (circles): Fg - fledgling, SbAd- sub-adult, Ad - adult, and the rates at which one age flows into others (arrows): ϕ1\phi_1ϕ1 survival of first year, ϕ2\phi_2ϕ2 survival of second and later years, ρ\rhoρ     fecundity. Note that although sub-adults do not reproduce, those that survive the year become adults and reproduce (see Kendall et al., 2019).