Program Description

The African manatee is the most endangered and least studied manatee species in the world. It lives in lagoons within equatorial rainforests, in rivers at the edge of the Sahara Desert, around coastal islands in the Atlantic Ocean, and in many other habitats in 21 countries along the Atlantic African coast, as well as over 2000 miles inland in rivers in Mali and Chad. Despite laws to protect them, the African manatees’ biggest threats are illegal poaching, accidental capture in fisheries (bycatch), and other human-caused threats such as entrapment behind dams and habitat destruction.

Dr. Lucy Keith Diagne has been studying the African manatee for over 10 years with the simple goal of increasing knowledge about the species to aid its protection and conservation. Accurate data collected consistently over multiple countries allows us to determine national as well as regional trends, and to bring people from different countries together to work to address threats. We are conducting a long-term collaborative project that includes field research and laboratory analysis components to assess manatee status and distribution throughout the species range. The resulting data and analyses provide much needed new information for the species, and will help improve management and conservation actions.

This project includes the following components:

• Distribution and habitat surveys to identify and protect important manatee use areas.
• Threat assessments to identify, quantify, and work to reduce threats such as illegal hunting, bycatch, entrapment by dams, and habitat destruction.
• Rescues of injured, entrapped or illegally captured manatees.
• Necropsies of dead manatees to determine cause of death and to collect samples to better understand African manatee physiology and health.
• Population genetics: we’re conducting the first range-wide genetics study of the African manatee to determine where distinct populations exist, to estimate population numbers, and to determine the diversity and relatedness of different manatee populations across Africa. This will help us learn which populations are in trouble, and which ones are doing well.
• Feeding ecology: using a technique called stable isotope analysis, we’re identifying the types of food resources eaten by manatees throughout the many varied ecosystems in which they live, which in turn will greatly benefit managers in knowing what types of habitat to protect. Unlike all other manatee species, African manatees have been shown to eat fish and mollusks (clams and mussels) in addition to plants.
• Longevity: we are conducting the first age determination analysis of African manatees using ear bones from carcasses. The technique has been used for Florida manatees for many years, but this is the first time this analysis has ever been conducted for African manatees. The oldest manatee we’ve aged so far was 39 years old. Knowing how long manatees live gives us an added insight into the life history of these enigmatic creatures.

The results of our analyses from the biological information we collect helps us to develop a more complete understanding of life history for manatees from several populations throughout West and Central Africa, and gives us information we need to conserve them.