What kind of animal is a dugong? We will explain its characteristics, ecology, and habitat. The dugong is a mammal distributed in the Indian Ocean and the Western Pacific Ocean, and this species is the only member of the dugong family. However, despite their vast habitat, their numbers are very small and they are in a critical situation.
What is a dugong? About basic status
Dugongs are mammals classified in the genus Dugong, family Dugongidae, order Dugongales. English is Dugong, scientific name is Dugong dugon. The body length is 3 meters and the weight is 450 kg. The list of information is as follows. Dugongs are also said to be “model mermaids”. Even in Pokemon, there is a monster called Dugong.
| Japanese（和名） | ジュゴン |
| English（英名） | Dugong |
| scientific name(学名) | Dugong dugon |
| classification（分類） | Mammalia、Sirenia、 Dugongidae、Dugong 哺乳綱、ジュゴン目、ジュゴン科、ジュゴン属 |
| IUCN Status(保全状況) | VULNERABLE |
| Length（体長） | 3m |
| Weight（体重） | 450kg |
About classification
The dugong is a mammal distributed in the Indian Ocean and the Western Pacific Ocean, and this species is the only member of the dugong family.
Dugong Taxonomy
- 界 (Kingdom)：動物界 (Animalia)
- 門 (Phylum)：脊索動物門 (Chordata)
- 綱 (Class)：哺乳綱 (Mammalia)
- 目 (Order)：海牛目 (Sirenia)
- 科 (Family)：ジュゴン科 (Dugongidae)
- 属 (Genus)：ジュゴン属 (Dugong)
- 種 (Species)：ジュゴン (Dugong dugon)
About habitat
Dugongs can be seen in tropical oceans such as the Indian Ocean, the Pacific Ocean, Australia, and the Red Sea. They can also be seen in the Philippines and around Okinawa in Japan. According to the documents, they are Sirenia and live in the natural ocean, so it is difficult to see them. Let’s take a look at some photos from the facility.
- Geographic Distribution
Dugongs live in shallow tropical and subtropical waters. Their main distribution areas are as follows:
East coast of Africa: Mozambique, Kenya, and Tanzania
Middle East: Persian Gulf coast
South Asia: India and Sri Lanka
Southeast Asia: Thailand, Malaysia, Indonesia, and the Philippines
Northern coast of Australia: Around the Great Barrier Reef
Pacific Islands: Papua New Guinea, Solomon Islands, etc.
- Habitat
Prefers shallow seagrass beds
Especially bays and lagoons with stable salinity
Mostly found in waters up to about 10-15 meters deep
Feeds on sandy or muddy seabeds
Does not particularly prefer rocky or steeply deep waters
- Behavior Patterns and Habitat Relationships
They may move depending on the distribution of seagrass.
They may form schools in isolated bays or shallow areas.
Breeding and rearing occur in calm, shallow waters with abundant seagrass.
feature is? What kind of creature is it?
The dugong has a spindle-shaped body with a very thick upper lip and a flat, rounded tip. The ear holes are small, and so are the eyes. The forelimbs are fin-like and have no claws, and the hind limbs are degenerated. Hair grows sparsely all over the body, and the body color is gray, brown, or bluish gray. Dugongs live in areas with coral reefs and can dive to depths of more than 35 meters.
- Physical Characteristics
Body Type: Rounded, thick body, streamlined, and easy to swim.
Size:
Body Length: 2-4 m
Weight: Approximately 250-400 kg
Skin/Fur:
Thick skin and almost no hair.
Back is gray to brown, belly is slightly lighter.
Head/Face:
Nose points upward, allowing for easy breathing at the surface.
Mouth points downward, allowing for efficient feeding on seaweed.
- Limb/Tail Characteristics
Pectoral Fins: Two in front, used for steering and turning.
Caudal Fin: Swims using a horizontal tail fin like a dolphin.
Perfectly adapted to underwater life.
- Diet
Completely herbivorous.
Main food: Seaweed.
Uses its mouth to eat seaweed from the roots found in the sand and mud on the ocean floor.
Consumes 5-8% of its body weight in seaweed per day.
- Behavior/Lifestyle
They are completely aquatic and never come onto land.
They are slow swimmers but have great stamina.
They are not very social, and often live in small groups (mothers and calves or a few individuals).
They surface every few minutes to breathe.
What is your personality like?
Dugongs have a very docile personality. However, they are also very nervous animals, and have exceptionally good hearing, allowing them to detect predators. Their activity times vary greatly depending on the time of day. They often dive in the subtropical coastal waters to search for food.
- Gentle and gentle
They are rarely aggressive and are timid and docile towards humans and other animals.
As they are nicknamed “sea cows,” they are characterized by their leisurely movements.
- Social
They may form herds, but in small groups (mothers and calves or small groups of several animals).
Adults often act alone.
Even within herds, they rarely fight and are peaceful.
- Cautious and wary
When they sense danger or humans, they will slowly flee, keeping their distance.
They rarely make sudden movements or attack.
They maintain safety by spending their time relaxing in shallow waters and seagrass beds.
- Laid-back and at their own pace
They move and eat very slowly.
They will feed on seagrass in the same place for long periods of time or rest on the surface.
They are active both day and night, but they live leisurely in shallow waters where they are less susceptible to predation.
What is the ecology like?
Dugongs are herbivorous and subsist mainly on seaweed such as eelgrass. There is no fixed breeding season, and the gestation period is 13 months. They can give birth to one cub at a time. Both males and females reach sexual maturity as early as 6 years. They have a very long lifespan, with some living for over 50 years, and some can live up to 70 years.
- Life Rhythm
Completely aquatic and never comes onto land
Resurfacing every few minutes to breathe
Slow-moving and capable of long swims
Active day and night, but often spends their time relaxing in shallow waters or seagrass beds
- Diet
Completely herbivorous (seagrass is their staple diet)
Seagrass:
Cycad, eelgrass, dugong grass, etc.
Eats 5-8% of their body weight in seagrass per day
During feeding, they submerge their heads in the seafloor and pull up the roots
- Reproduction and Rearing
Breeding Season: Varies by region; in Australia, they breed almost year-round
Gestation Period: Approximately 13 months (long!)
Litter Size: Usually one calf
Rearing:
Mothers protect their calves, nurse them, and teach them how to swim
Mothers and calves stay together for several months to a year
- Movement and Living Range
Move mainly to shallow waters with seagrass beds
When gregarious, Mothers and children, small groups
Home ranges vary depending on seagrass distribution
Are there any natural enemies?
Dugongs’ natural enemy is sharks. Killer whales are also very large prey. Looking at a lot of research and survey data, there is a possibility of extinction because there is no defense against these things.
About Dugong Baby Animals
This article provides detailed information about dugong (Dugong dugon) baby animals.
- Birth and Body Size
Litter Size: Usually one pup (twins are extremely rare)
Weight: Approximately 30-35 kg at birth
Body Length: Approximately 1 m at birth
Skin/Fur: Almost hairless, soft gray skin
- Growth
Lactation: Breastfeeds for approximately 1-2 years
Independence: Learns how to swim and eat seaweed with the help of its mother’s care
Adult Body Size: Reaches nearly adult size at 3-5 years
Maturity: Sexual maturity is very slow, occurring at approximately 10-15 years
- Behavior
Immediately after birth, they stay with their mother
Learns how to swim by watching the movements of their mother’s pectoral and caudal fins
Learns how to eat seaweed from their mother
Hides near their mother when sensing danger
- Personality and Behaviors
Young pups They are curious and playful.
However, they are also cautious and will quickly hide near their mother if they sense danger.
They are highly dependent on their mothers and it takes a long time for them to become independent.
- Caution (Dangers to Young Animals in the Wild)
Natural predators include sharks and crocodiles.
Habitat destruction and human activity have led to a low survival rate.
Protecting mothers and young animals directly contributes to habitat conservation.
Is the dugong an endangered species?
Dugongs are designated as an endangered species (red list). Their meat is edible and considered very delicious, leading to overfishing. Furthermore, marine pollution and the resulting decline in seaweed, which serves as their food, have also dealt a major blow. In Japan, they were designated as a national natural monument in 1972, and since 2003, the Wildlife Protection Act has prohibited their capture and killing, in principle. Dugongs are also listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), so international trade is strictly restricted. In the ocean, efforts are underway to conserve wild sea cows.
- Conservation Status (Endangered Species Classification)
IUCN Red List (International Union for Conservation of Nature):
Vulnerable (VU) = Equivalent to Critically Endangered
Rated “high risk of extinction in the wild in the future.”
Regional Differences:
Relatively stable in protected areas such as northern Australia.
Populations are declining in Southeast Asia and South Asia, and are locally endangered.
- Causes of Extinction
Habitat Destruction
Coastal Development, Port Construction, and Seagrass Bed Reduction
Seagrass reduction leads to food shortages and makes survival difficult.
Collisions with Fisheries
Frequent entanglement in fishing nets
Injuries and deaths caused by fishing gear have been reported.
Poaching
In some areas, meat, oil, and bones are traditionally used.
Collisions with Ships
Injuries can occur in shallow waters where ships pass.
- Conservation Activities
Protection of seagrass beds and coastal areas, and fishing regulations are being implemented.
Wild population monitoring and the establishment of protected areas are progressing.
Can dugongs be kept as pets?
Dugongs live in very harsh conditions, and due to the effects of development in society, it is extremely difficult to keep them in captivity. We recommend viewing them at aquariums. In recent years, there have been reports of them being seen in the wild along coastlines, so you can see them swimming along the coastal areas of the ocean with manatees and other creatures.
- Legal Issues
Dugongs are listed as an endangered species (IUCN: Vulnerable)
Listed under Appendix I or II of the international treaty CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora),
Commercial and private captivity is generally prohibited.
Keeping them without special permission is illegal.
- Biology and Personality
They are fully aquatic and do not come onto land.
They require large, shallow waters and seagrass beds.
Adults are very large, weighing 250-400 kg,
making it physically impossible to keep them in a home or aquarium.
They are gentle but timid and sensitive to stress.
- Difficulties in Care
They require large amounts of seagrass (5-8% of their body weight per day).
They require a high level of exercise, requiring a spacious aquarium or marine environment.
Breeding is extremely difficult due to their long breeding period (13 months of gestation, 1-2 years of lactation).
- Alternatives
If you want to see dugongs up close,
Observing them at an aquarium or conservation facility is the most practical option.
Learning about the ecology of wild individuals also contributes to their conservation.
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