African Manatee, Trichechus senegalensis
The African manatee (Trichechus senegalensis) is thought to be similar to the West Indian manatee. Its other common names include the seacow and the West African manatee. It is native to Africa, specifically Senegal to Angola and West Africa. Its range also includes Mali, the Democratic Republic of the Congo, and Ghana, among other regions. They can live in many water habitats including freshwater, oceans, brackish water, and lagoons. However, they will not live anywhere with a temperature lower than 64.4 degrees Fahrenheit.
In some coastal areas of West Africa, African manatees dwell in the central-eastern and southeastern areas of the Atlantic Ocean, swimming as far out as 47 miles. These manatees also reside in lakes, including Lake Léré, the Inner Niger River Delta in Mali, and Lake Volta. Because flow rates and water levels change within rivers, some of the lakes they inhabit serve as refuges during dyer months. Rivers the African manatee inhabits include the Senegal, Gambia, Tombali, Great Scarcies, Little Scarcies, and St. Paul, among many others. The manatees will swim as far upriver as possible, until they encounter shallow waters or powerful waterfalls that impede passage.
Naturalist Johann Heinrich Friedrich Link first classified the African manatee as a species in 1795, under the name Trichechus senegalensis. There are no recognized subspecies of this manatee, although rumors have occurred stating that some populations of manatees that reside in isolated inland waters vary morphologically from coastal manatees. After some investigation, this was found to be untrue. The African manatee was placed within the Trichechus genus along with Amazonian manatee and the West Indian manatee.
The African manatee is similar to the West Indian manatee, although the two are distinct species. Both must have an area of water that is secure, with abundant food and freshwater resources. The most populated areas where the African Manatee resides include Guinea-Bissau, Sanaga River, and southern portions of the Niger River, the lagoons of Ivory Coast, the lower areas of the Congo River, and the coastal lagoons in Gabon.
The African manatee can be described as round in shape, with a flat tail. It can reach an average body length of 14.6 feet, with an average weight of 790 pounds. Adults are gray in color, bearing short hairs with no color on the entire body, while young manatees are born very dark. Algae can build up on the manatee’s body, giving it a slight brown or green color.
Because of its large size, the African manatee travels at slow speeds, reaching only three to five miles per hour. When threatened, they can move as fast as twenty miles per hour. The large, flat fins of the manatee are used for propulsion and food consumption. The flippers, which hold short nails, are also used to “touch and embrace” other manatees. The manatee does not have any hind limbs.
The African manatee is nocturnal, being most active at dusk and during the nighttime. It remains silent as it forages for food. When resting during the day, this manatee will remain in shallow water reaching depths between 3.2 feet and 6.5 feet. Typically, manatees will live in small groups numbering up to six individuals, and it is thought that this occurs due to threats from large, natural predators like sharks and crocodiles. In countries like Sierra Leone, the African manatee will migrate during flooding season in June and July. When flooding occurs, the salinity of waterways and food abundance decreases.
It is difficult to distinguish the sex of the African manatee, as the only differences between them are a slight size variance and the genital openings on the underbelly. Males reach sexual maturity at nine to ten years of age and females can mate at two or three years of age. They are capable of mating year round, although typically only one calf is born every three to five years. Females will mate with many males, and males will fight for the chance to mate, pushing and shoving their way to the female. Although little is known about the social structure of a manatee group, the closest relationship is most likely found between a mother and her calf.
There are local legends about the African manatee that differ in content. In western Africa, it is known as Maame (or mami) water, appearing in many coastal legends as a “goddess” of the sea and a symbol of beauty and wealth. However, Maame water is also known to turn boats over. After conducting research, scientists from the Institute of Aquatic Biology of the Centre for Scientific and Industrial Research (CSIR) and the Wildlife Department in Ghana have found that the African manatee is most likely the legend Maame water. When looking at a manatee, it can appear to be human when jumping out of the water or surfacing for air. Speaking of the legend is taboo, unless it occurs after specific ceremonies. In Nigeria, legends speak of those who marry a Maame water mermaid, gaining great fortune only to lose it after being unfaithful.
Despite the interesting legends about the African manatee, it is still hunted for its meat, bones, skin, and oil. Poachers hunt the manatee, and they are also sold locally and online as pets, as well as to zoos and aquariums. The manatee has been given a conservation status of “Vulnerable” on the IUCN Red List, but due to a lack in law enforcement, poachers are still able to hunt the African manatee. In Mali and Chad, locals depend on the oil from the manatee to cure ailments such as rheumatism and ear infections.
The Africa manatee is also threated by habitat loss due to urban developments and expansion, and because of increased boat travel through many of the manatee’s natural waterways, many manatees can lose their lives from boat motor run-ins. Occasionally, manatees can become stuck in fisher’s nets, and when this occurs many fishers will kill the manatee before it can cause serious damage to their nets. The manatees have also been known to swim into rice fields during flood seasons, destroying precious food.
The West African Manatee Conservation Project completed Phase 1 of a plan to help save the African manatee between the years of 2004 to 2007. The countries of Mauritania, Senegal, The Gambia, Guinea, Guinea Bissau and Sierra Leone amassed information about the current populations of the African Manatee residing in these regions by holding surveys throughout each country. This process was extremely successful in spreading knowledge and awareness of the African manatee, allowing students and scientists alike to better understand the species. Wetlands International plans to enact Phase 2 because of this success, spreading the known information into even more areas of the African Manatee’s range.
Image Caption: African Manatee in the Toba Aquarium, Japan. Credit: Wikipedia(CC BY-SA 2.5)