The calf begins to nurse within a few hours after birth by suckling from a teat under the pectoral flippers. Calves nurse underwater. Calves begin nibbling on plants within a few weeks of birth. Although it may be weaned by the end of its first year, the calf remains close to its mother for up to two years. Manatees probably live a maximum of 50 to 60 years.
Manatees are very susceptible to cold weather.
It's not unusual for many to die during extremely cold weather. Due to their dark color and because they are slow swimmers, manatees are difficult to see in the water. Many manatees are injured and killed by propellers and hulls of speed boats. Collisions with boats and barges is the largest human related factor causing manatee death in Florida. The Florida manatee is one of the most endangered marine mamals in the United States.