Dugongs: An Endangered Marine Species
Dugongs are large marine mammals which are one of the four living species of the order Sirenia or sea cows as they are commonly referred. The order evolved more than 50 million years ago. Dugongs now inhabit marine waters in 43 Indo-Pacific countries but are considered an endangered species.
• National Geographic: Dugong profile and pictures
• Center for Biological Diversity: Natural history of the Dugong
• Buena Vista Museum of Natural History: Fossil history
Relatives
Dugongs are related to manatees, similar in behavior and appearance. They are also distantly related to the elephant although they do not look or act like them.
• UNEP: Similarities and differences of the manatee and dugong
• University of Michigan: Sirenian classification
Physical Traits & Behavior
With blubbery bodies, unusually shaped heads, and dolphin-like tails, dugongs were once mistaken for mermaids by sailors. Their huge rough lips and unique teeth are designed for eating sea grass. Dugongs are social with one another but are known for being shy around humans. They communicate with one another through bird-like whistles and chirps.
• Roberto Sozzani: Dugong behavior
• Missouri Botanical Gardens: Physical traits of the dugong
• The Animal Files: Main dugong characteristics
Habitat
Strictly marine mammals, dugongs are found in coastal habitats in shallow areas of bays, mangrove channels and sides of large inshore islands where sea grass grows. The largest dugong population is in Australia’s northern waters.
• The Humane Society: World habitat
• Australian Government: About Australian dugong habitat
Diet
The dugong is a herbivore who sticks to a diet of over 15 types of sea grass, eating up to 20 pounds a day. They graze the bottom of the ocean for their food and have specialized features such as a dense heavy skeleton that helps keep them at the bottom. They can stay underwater six minutes before surfacing. Dugongs leave a sandy feeding trail in their wake. It takes over a week for dugongs to digest their food.
• Marine Bio: Feeding behavior
• Wild Singapore: Dugong diet information
Reproduction
Dugongs do not start mating until they are 9 to 10 years old and then only reproduce every 3 to 7 years. The typical pregnancy term is one year and only one calf is given birth to at a time. Dugong babies nurse for up to 18 months and stay close to their mothers for several years.
• ABC Science: Dugong mating
• Ocean Ambassadors: Population facts
Conservation Status
After thousands of years of being hunted for their meat and oil, the dugong population has reached endangered status. Conservationists around the world have called for an end to dugong hunting and are trying to protect the dugong’s habitat from industry. Even with conservation efforts in place, many of the world’s dugong populations are near extinction.
• Edge of Existence: Dugong conservation efforts
• Earth’s Endangered Creatures: Endangered status and locations
• American.edu: The Persian Gulf dugong threats
• The IUCN Red List: Dugong threatened status and assessment information