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Dugong

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The dugong (*Dugong dugon*) is a large marine mammal belonging to the order Sirenia. This order also includes three species of manatees, but the dugong is unique. It is the only living member of the family Dugongidae. Its closest relative, the Steller's sea cow, was hunted to extinction during the 18th century.

dugong
dugong

Dugongs are strictly marine animals, meaning they live entirely in saltwater. This differs from manatees, which use freshwater environments. They play a vital role in coastal ecosystems by feeding on seagrass. Because they rely so heavily on these underwater meadows, their survival is tied to the health of the sea floor.

A dugong's body is designed for life in the water. It has a fusiform shape, which means it is cylindrical and tapers at both ends.

Dugong - underside
Dugong - underside

To move, it uses a tail with flukes, similar to a dolphin. These flukes move in long up-and-down strokes to push the animal forward. For steering and slowing down, the dugong uses paddle-like forelimbs called flippers.

Dugong dugon fin egypt
Dugong dugon fin egypt

Interestingly, the dugong experiences pachyostosis. This is a condition where the ribs and long bones are unusually solid and heavy. These dense bones act like ballast, helping the animal stay suspended just below the water's surface.

The dugong has specialized anatomy for eating seagrass on the ocean floor. Its snout is sharply downturned, which is an adaptation for feeding in benthic communities.

It also possesses a large, muscular, horseshoe-shaped upper lip. This mobile muzzle helps the animal forage through the sand and grass. Unlike manatees, dugongs have simple, peg-like molar teeth. Males also develop two incisors, often called tusks, during puberty.

DugongForelimbSkel
DugongForelimbSkel

These tusks can help with feeding and social interactions.

Scientists have traced the history of Sirenians back about 50 million years to the Eocene epoch. While the order once had more diversity, populations declined due to oceanographic changes and climatic cooling.

dugong
dugong

The name "dugong" comes from the Visayan language. The French naturalist Georges-Louis Leclerc, Comte de Buffon, popularized the name in his 1765 work, *Histoire Naturelle*. In 1776, the scientist Müller first classified the animal as *Trichechus dugon*. Later, researchers like Lacépède and Gray helped establish its place in its own unique family.

Today, dugongs live in warm coastal waters across the Indo-West Pacific. Their range spans the waters of approximately 40 countries and territories.

Dugong mother offspring
Dugong mother offspring

They prefer wide, shallow, protected areas like bays, mangrove channels, and inter-reefal waters. The northern waters of Australia, specifically between Shark Bay and Moreton Bay, are considered a major stronghold for the species.

DugongAreaMoretonBay
DugongAreaMoretonBay

While they usually stay at depths of about 4 meters, they can travel deeper to find specific seagrasses.

Despite their importance, dugongs face serious threats. The worldwide population has declined by about 20 percent over the last 90 years.

Dugong Lamen Island Epi Vanuatu
Dugong Lamen Island Epi Vanuatu

Many populations are fragmented and close to extinction. The IUCN lists the species as vulnerable. Major causes of decline are anthropogenic, which means caused by humans. These include habitat degradation, hunting, and fatalities related to fishing. Because dugongs have a long lifespan of 70 years or more and a slow rate of reproduction, it is difficult for their numbers to recover quickly.

Evolutionary studies show that dugongs are not closely related to other marine mammals like whales. Instead, they are more closely related to elephants. They belong to a group that also includes hyraxes and aardvarks. This connection is visible in their status as placental mammals.

Dugong mother offspring
Dugong mother offspring

Molecular studies using mitochondrial DNA have even shown that different populations, such as those in Southeast Asia and Australia, have distinct genetic lineages. This helps scientists understand how these unique sea cows have moved through the oceans over millions of years.

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🖼️ Images & Media (12)
File:DugongForelimbSkel.jpg
DugongForelimbSkel.jpg
File:Dugong dugon fin egypt.jpg
Dugong dugon fin egypt.jpg
File:Dugong - underside.jpg
Dugong - underside.jpg
File:Dugong Lamen Island Epi Vanuatu.jpeg
Dugong Lamen Island Epi Vanuatu.jpeg
File:dugong.jpg
dugong.jpg
File:DugongAreaMoretonBay.jpg
DugongAreaMoretonBay.jpg
File:Untitled - panoramio - karlee ladyk (23).jpg
Untitled - panoramio - karlee ladyk (23).jpg
File:Dugong Marsa Alam.jpg
Dugong Marsa Alam.jpg
File:Dugong in Ritchies archipelago Neil Island Andaman.jpg
Dugong in Ritchies archipelago Neil...
File:Dugong mother offspring.jpg
Dugong mother offspring.jpg
File:Ipoh-tambuncave-dugong.jpg
Ipoh-tambuncave-dugong.jpg
File:Stamp of Indonesia - 2005 - Colnect 385149 - Dugong Dugong dugon.jpeg
Stamp of Indonesia - 2005 - Colnect...
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