Lifespan, longevity, and ageing
Maximum longevity: 56 years (captivity) Observations: Laboratory studies show that males are physiologically capable of mating when they are 2-3 years old. In the wild, however, they appear to reach full sexual maturity at the age of 9-10 years (Ronald Nowak 2003). Manatees may also feature some form of continuous tooth development (Caleb Finch 1990). One 56 year old male was still alive in captivity (Richard Weigl 2005). Another specimen was estimated to be 59 years old in the wild (Ronald Nowak 1999).