Female manatees give birth to one live calf every 2-5 years. A female can give birth to twins, although this is rare. If a cow (female manatee) aborts or loses her calf, she can conceive sooner and give birth to another calf in just one year. At birth, a Florida manatee calf measures about 1.2-1.4 meters (4-4.5 feet) and weighs 27-32 kilograms (60-70 lbs.). The calves are born with either their tail or head first. Manatee live births commonly happen during summer and spring, but breeding occurs year-round. After birth, a calf remains close to the mother for about 1-2 years. However, some are weaned earlier and gain independence by the end of the first year.
Caring for manatee babies
Newborn calves swiftly swim to the surface for their first breath. Additionally, they emit vocalizations at or shortly after birth, which fosters bonding between mothers and calves. Within a few hours, calves start nursing by suckling from the mother’s teats beneath the pectoral flippers. The milk, predominantly water, contains 20% solids, 13% fat, and 7% protein. Throughout this period, calves remain close to their mothers until weaning. Once they transition to eating sea grass instead of nursing, calves become independent, freeing mothers to breed again.
Responsibility for raising calves
Female manatees have full responsibility for nursing and raising the calves. Nursing of manatee calves takes place underwater with the babies suckling from the nipples located behind the front flippers. The calves depend on their mothers for nutrition and for learning about resting areas, feeding, warm water refuges and travel routes. While manatee calves start to nibble plants within a few weeks after birth, they learn gradually and are often weaned and left on their own after 2 years.
Rate of live births
The rate of reproduction is quite low in manatees. Both male and female manatees are usually sexually mature at the age of 5, with one calf born every 2-5 years. With a gestation period of about 13 months, an interval between births of 2-5 years and the birth of twins being rare, manatee populations tend to grow slowly. However, because manatees don’t have natural enemies and can live up to 60 years or more, their slow birth rate has little effect on their population. For more information on manatees, manatee tours and memorable swimming and kayaking experiences with manatees, visit the “Captain Mike’s Swimming With The Manatees” site.
References:
- Seaworld. (2018). Birth & Care of Young Manatees. Retrieved from https://seaworld.org/animals/all-about/manatees/care-of-young/