Fig. 2. Relationship between level of harvest and probability of quasi-extinction for kereru after 30 yr under two different harvesting strategies. Harvest levels are defined by: (1) the proportion of adults removed in the prebreeding harvest scenario (dotted line), (2) an equivalent number of birds made up of equal numbers of adults and juveniles in the postbreeding harvest scenario (solid line), and (3) a density-dependent (D-D) harvest that describes what happens if adults and juveniles are taken in proportion to their relative availability, based on the stable age structure in the population (dashed line).