Mortality rate, expected lifespan, and maximum lifespan estimated from observed survivorship records of a cohort of 150 <i>M</i>. <i>hartmanni</i> colonies from a single population at Stengl Lost Pines Biological Station surveyed annually in late spring or early summer between 2000–2007 until all colonies had died.

Maximum lifespan is defined as the timepoint at which 95% of colonies of a cohort are expected to have died. The four Estimates 1–4 are based on models that differ in modeling assumptions. Mortality was assumed to occur only outside the annual re-survey season April-July (Estimates 1 and 3); or alternatively, mortality risk was assumed to be constant across all days of the year including the re-survey months April-July (Estimates 2 and 4). Estimates 1 and 2 ignore differences in sample sizes across years (later years have naturally smaller sample sizes because of nest mortality), while Estimates 3 and 4 weigh confidence in the mortality rates across years by the number of individual nests at the start of a given census interval (additional details in Materials and methods).