Dugongs and Manatees: The Mythical Mermaids?

Mermaids. The mythical creature with great seductive powers. The femme fatale, with the head and upper body of a female human and the tail of a fish.

As long as there have been seafarers, it seems, there have been mermaids to mess the minds of these intimacy deprived sailors.  

The male equivalent of the mermaid is the merman. The male and the female collectively are sometimes referred to as merfolk or merpeople.

Do these seductive creatures really exist?  Maybe in form of Dugongs and Manatees which have breasts and suckle their young ones above water, in human fashion. 

When dugongs surface to breathe, they sometimes “stand” on their tail with their head above water. With poor lighting, imaginations and of course dry spell, to the sailor this looked like the head of a beautiful seductive lady..

Dugong also known as sea cow, is known as Nguva in Swahili. It has a simple scientific name: Dugong dudong. They are found tropical waters from East Africa to Vanuatu, about 26 degrees both north and south of equator. They are only found in the salty waters of the oceans. They are the only exclusively marine mammals that are herbivorous. In Kenya Dugongs have been sighted in Kiunga Marine Park. 

          In serach of the dugongs in India Ocean

On the other hand, Manatees are found in shallow, slow moving rivers, estuaries, saltwater bays, canals and oceans. They live in both freshwaters and saltwaters of the Caribbean Sea, Gulf of Mexico, Amazon basin and West Africa. 

Even though the dugongs and manatees are marine mammals, they are more closely related to elephants than dolphins or whales. 

The key difference between the dugongs and manatees are: 

Tail shape

Dugong tails have flukes made up of two separate lobes joined together in the middle and look similar to whale or dolphin tales. 

Manatees have a horizontal paddle-shaped tail with only one lobe to move up and down when the animal swims.

Mouth shape

Dugongs have a longer, broad, short trunk-like snout and agile upper lip used to munch on seagrass. It faces downward with a slit for a mouth, useful for feeding off the ocean floor. 

Manatees have a divided upper lip and a shorter snout.  They are able to both gather food and feed on plants growing at or near the surface of the water. 

Body size

Manatees are larger and can grow up to 4 metres (13 feet) long.

Dugongs are smaller and rarely get larger than 3 metres (10 feet) long.

Habitat 

Dugongs never leave saltwater. They spend their entire life in shallow, sheltered coastal areas such as bays and mangrove swamps.

Manatees, on the other hand, can be found both in fresh and saltwater. West Indian and West African reside primarily in salt water but migrate to warmer freshwater areas in the winter. The Amazonian manatee lives only in fresh water.

Teeth

Dugongs have overgrown incisors set at the front of the mouth that resemble small tusks. They are well developed and only visible in adult males and old female dugongs.

Manatees do not have the ‘tusks’. They have the marching molars (hind molar progression). Manatees constantly grow molars in the back corners of their mouth. As the front teeth grind down and eventually fall out, the molars fully emerge, pushing new teeth forward

Reproduction

Dugongs have a very long reproductive cycle. Female dugongs start conceiving at the age of  10 years. They only give birth every three to seven years. 

Female manatees typically have their first baby at age three and have more babies every two to three years.

Manatees are devout polygamists. A male manatee can have several female partners.

Dugongs, on the other hand, have different sexual lifestyles depending on the locality. In some areas, they are monogamous with only one mate, and they live as a couple for life. In other areas they are polygamist and polyandrous. They even display a mating behavior similar to lekking -  a lek is a traditional area where male dugongs gather during mating season to participate in competitive activities and displays to attract females.  

Once they success in attracting the female, they proceed through three phases.  In the following phase, a group of males follow a single female attempting to mate with her. This prompts the fighting phase whereby the males fight to determine who will mount the female. The winner enters the mounting phase where he mounts the female from underneath as the losers continue to fight for mating rights. The male is thus mounted several times by the competing males. This almost guarantees conception.