Descriptive statistics of the data used in the analyses (stillbirth and liveborn survival models) of Asian elephants illustrating the sample size and data completeness.

Initial sample includes all calves born to captive-born mothers before year 2000 n = 1138. Follow-up percentage refers to the percentage of elephants in the initial cohort included in the final analyses due to the exclusion of individuals with missing or erroneous data. ‘Short’ interbirth interval refers to cases where the previous birth-interval length was 6.6 years (75% quartile) and ‘firstborn’ if the calf was first to its mother. Note that logging area (n = 32) instead of region (n = 8) was used in the statistical models, but values for regions are shown here for simplicity. Firstborn/Missing-category for interbirth interval length includes all firstborns (n = 404) and 23 laterborns with missing birth-interval information.