Figure 4.

Results of separate subpopulation analyses of Hawaiian monk seal survival rates. Age groups found to have significantly different survival rates are plotted separately, showing an increase in survival with age until senescence is expressed. Gender differences in survival were found only at French Frigate Shoals. Box plots show the distribution of point estimates of survival rates over time. The lower boundary of the box indicates the 25th percentile, a line within the box marks the median and the upper boundary of the box indicates the 75th percentile. Error bars indicate the 90th and 10th percentiles. Horizontal lines alone indicate single-point estimates where time variation was not detected. At Laysan Island, significant temporal variation was detected in the age group of 18–21 years and the four available estimates are shown in lieu of a box plot.