American Oceans

What’s the Difference Between a Dugong and a Manatee?

Although they are both commonly referred to as sea cows, there are differences between the dugong and the manatee.

dugong swimming

They are closely related, but how can you tell the difference between the two?

When it comes to the dugong vs manatee differences, habitat, appearance, size, and social lives play huge roles in differentiating the two.

Dugongs and manatees are both fascinating creatures, but unfortunately, both are also listed as vulnerable species, which means that their numbers are declining and they require human assistance to get their populations back up and to thrive again.

Read on to learn all about these fascinating creatures!

What Is a Dugong?

The dugong, or Dugong dugon, is the only living member of the Sirenia order left in the Pacific ocean.

Dugong eating from the sandy bottom

Although it is closely related to the manatee, dugongs do not ever venture into freshwater. They are the only herbivorous marine mammals to live only in saltwater. 

Coastal peoples have known about dugongs for millennia, but the species only received a genus and species classification in 1776. They are also known as sea pigs and even sea camels. 

Dugongs live in the coastal waters of Australia as well as the Great Barrier Reef, shallow waters in the Indian and Pacific Oceans, or along the strip of the East African coast, where there is a small human population. 

Dugongs are also an indicator species. If the local population of dugongs is healthy and thriving, other species that call those areas home are also doing well. If the dugong population is declining or all but gone, that is a huge warning sign for those waters that the ecosystem is suffering damage.

What Is a Manatee?

There are three types of manatees: the West Indian manatee (Trichechus manatus), the West African manatee (Trichechus senegalensis), and the Amazonian manatee (Trichechus inunguis). 

manatee close up

Like dugongs, manatees are part of the order Sirenia, and these three species of manatee represent three out of four of the remaining Sirenia species (the fourth being the Dugong dugon).

Manatees have only six cervical vertebrae, whereas all other mammal species except two types of sloth have seven. Manatees were given their Latin classification in 1758.

Manatees, like dugongs, are also known as sea cows. They gently and slowly meander across fields of seagrass, munching away like cows all the while. 

Unlike dugongs, manatees live in freshwater and saltwater areas. They inhabit the waters of the Gulf of Mexico, shallow swamps and rivers along the Gulf Coast, the northern coast of South America, and the waterways and tributaries of Central America.

They are often seen in Florida and sometimes Alabama.

Dugong vs Manatee

How can you tell a manatee apart from a dugong? There are some key differences, although they do have many overlapping traits.

Appearance 

Although it may not be apparent at first glance, most dugongs have small tusks on each side of their mouths. 

manatee underwater
manatee

Dugongs are smaller and even slimmer than manatees, while manatees tend to have a rounder, chunkier appearance. Dugongs have a downturned, longer snout than manatees have, while manatees have no incisors or molars and instead simply have cheek teeth.

Another obvious difference is the tail shape. As mammals, manatees and dugongs both have horizontally-aligned tails, but they are shaped differently.

A dugong’s tail resembles that of a dolphin, while manatees have rounded, paddle-like tails more like beavers. Both dugongs and manatees have paddle-like flippers.

Size

Dugongs tend to reach a maximum of 9 feet long, or about three meters. Manatees can reach lengths of about 13 feet, or almost four meters long.

Dugong rising to the surface for air
Dugong rising to the surface for air

Manatees typically weigh anywhere from 800 to 1,200 pounds (360 to 545 kilograms), while the dugong ranges in weight from 550 pounds to 880 pounds (250 to 400 kilograms). 

Although dugongs can weigh more than manatees, it is rare for a dugong to reach that size.

The smaller end of the range is typical for dugongs, which makes them appear slimmer but longer compared to manatees. 

Habitat

Manatees and dugongs prefer shallow coastal waters because their favorite foods grow there.

manatees at Crystal River FL
Manatees at Crystal River Florida

However, dugongs have a territory that ranges from a bit of East Africa, the Red Sea, and Australia, while manatees range from the Southern United States in rivers and mangrove swamps and all the way up to West Africa and down to Central and South America.

Dugongs are thought to be mostly concentrated in Australia’s Shark Bay and Moreton Bay. 

Although manatees seem to have a wide habitat range, there are no manatee populations in all of those areas. They migrate, breaking the population into small groups throughout those regions.

Behavior

Dugongs have small brains in comparison to their large bodies because they did not have to evolve a specialized brain capable of hunting or evading predators.

Calm dugong near the ocean surface
Calm dugong near the ocean surface

They spend most of their time grazing along meadows of seagrass, much like terrestrial cows. 

Manatees do the same, resting, feeding, and moving in directions where they know they can find food.

Manatees and dugongs have to find food and stay in warm waters, but manatees have a larger habitat range than dugongs.

Diet and Feeding 

Dugongs and manatees are both herbivores.

dugong eating sea grass
dugong eating sea grass

Dugongs feed mainly on sea grass, whereas manatees love all types of marine plants, including sea clover, kelp, algae, sea grass, and dozens of other types of aquatic vegetation.

Lifespan

Dugongs can live for up to 70 years. Female dugongs can even keep reproducing into their 30s and 40s. West Indian manatees, also known as Florida manatees, can live 60 years or more.

Manatees and dugongs can live long lives as long as threats from humans do not cut those lives short.

Mating

When male dugongs are ready to mate, they will sprout tusks, signifying that testosterone levels are optimum.

Manatee Mating Frenzy
Manatee Mating Frenzy

Male dugongs use their tusks to fight each other and can even injure the females while fighting or attempting to mate. Females mate with multiple partners.

Male manatees will gather around a female manatee in estrus and usually compete to mate with her. Female manatees, like dugongs, have several sexual partners.

Female manatees only breed once every two or three years since weaning babies can take up to two years. 

Social 

Manatees tend to be solitary creatures, but can still cluster in groups. This is especially common if there are baby manatees still with their mothers and if food is plentiful in the area. 

colony of sea mammals Dugongs
colony of Dugongs

Dugongs are more social than manatees, clustering frequently in pairs, although they spend the majority of their time alone. Dugong mothers spend around a year and a half nursing their babies. Mother and baby only separate when the baby has matured, which can take up to four years.

Frequently Asked Questions

Here are some fun facts about dugongs and manatees for novice marine mammal enthusiasts and experienced sea cow lovers.

Were dugongs and manatees really the source of mermaid sightings?

Strangely, these chubby, slow-moving, and endearingly clumsy-looking sea cows were the inspiration for many mermaid sightings throughout history. In fact, the Malay word for dugong means “lady of the sea,” and researchers have found 3,000-year-old cave drawings depicting these sea cows.

How slow are dugongs and manatees?

Manatees typically move along at an average speed of 5 miles or 8 kilometers an hour. They can show bursts of speed underwater, but only for short “sprints.” Dugongs swim an average of 6 miles per hour or about 10 kilometers an hour.

Do dugongs have poor eyesight?

Dugongs do have poor eyesight, but their hearing is excellent. Because they feed on seagrass found in coastal waters, they do not need to rely on their sense of sight to find food, as seagrass is plentiful in their preferred habitats.

Are dugongs and manatees endangered? 

Both dugongs and manatees are on the list of vulnerable species. This means they fall under the threatened umbrella, but they are not endangered or critically endangered. Because of their long gestation periods, populations are having trouble keeping up with damage from humans.

How long can dugongs and manatees breathe underwater?

Manatees and dugongs are mammals and cannot breathe underwater. Manatees stay submerged in the water and come up for air every three to five minutes, although it can be as much as twice a minute if they’re expending a lot of energy. Dugongs come up for air just as frequently.

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