Lifespan, longevity, and ageing
Maximum longevity: 73.1 years (captivity) Observations: These are long-lived animals that appear to show indeterminate growth. In captivity, they can reach sexual maturity at 6 years of age. In the wild, food availability influences growth and sexual maturation with food scarcity being linked to a slower growth and a delayed maturity (Lance 2003). A decline in egg production in females over 30 years of age has been reported (Castanet 1994).