The 5.5-year-old female Caribbean manatee which lives together with a 17-year-old male in the Mangrove of Royal Burgers' Zoo is pregnant. Biologists and zookeepers of the Arnhem Zoo expect the birth to take place in January or February 2019. An exact date is difficult to determine: Caribbean sea cows have a gestation period between 12 and 14 months.
The biologists and zookeepers are assuming that the female West Indian manatee is pregnant, because she has a large bulge near the vulva, and no mating has been observed in a long time. There is no certainty because it is difficult to perform an ultrasound on an aquatic mammal of this size. Since a few weeks, however, her nipples are also clearly visible, which seems to indicate that the birth is imminent.
Royal Burgers' Zoo is the only zoo in the Netherlands that has manatees, and the last births there were in 1993 and 1995, so it will be a rare birth. Manatee births are also rare throughout the rest of Europe. A total of only 35 West Indian manatees live in European zoos: 21 males and 14 females.
Female manatees are normally sexually mature at about five years of age and males at nine years. Mating and births take place all year round, but in the summer months, there is a peak in the number of births. In the more temperate regions, the manatee imposes a mating stop during the winter.
Two subspecies of the West Indian manatee are distinguished in the wild: the Antillean manatee Trichechus manatus manatus and the Florida manatee Trichechus manatus latirostris. Both subspecies have been classified as 'endangered' by IUCN, while the species itself is classified as 'vulnerable' because of the long gestation period (12 to 14 months). Additionally, because a young stays with its mother for about 2.5 years, West Indian manatees do not often have young, and the population does not grow fast in the wild.