DUGONG AND SEA COW – Dugongidae

DUGONG AND SEA COW

DUGONG AND SEA COW FACTS

The near-hairless dugong and sea cow can be as long as 9.8 feet (3 meters) for the dugong and from 23 to 33 feet (7 to 10 meters) for Steller’s sea cow. They have no hind limbs, and the tail is forked, similar to that of a whale. Their front limbs are flipper-like and without nails. Dugongs are found in various colorations of gray and brown, though it is unknown what color the sea cow was. Dugongs can weigh more than 881 pounds (400 kilograms), and scientists estimate that Steller’s sea cow weighed more than 9,920 pounds (4,500 kilograms).

GEOGRAPHIC RANGE

Dugongs live in the tropical and subtropical Indo-Pacific. Steller’s sea cow was found in the western North Pacific Ocean.

DUGONG AND SEA COW HABITAT

Dugongids live in coastal waters that contain sea grass. Steller’s sea cow lived with macroalgae, large, plant-like algae (AL-jee) also called kelp.

DUGONG AND SEA COW DIET

Dugongs primarily feed on sea grasses that grow on the ocean’s floor in shallow water. Steller’s sea cow reportedly fed on the surface and was never recorded as diving. Because the sea cow was toothless, it had to crush its food between studded plates at the front of their upper and lower jaws.

BEHAVIOR AND REPRODUCTION

Dugongs are semi-social and can be found in units that include the mother and her most recent calf. These pairs have been known to live together in herds of up to hundreds when sea grass is abundant. Not much is known about Steller’s sea cow behavior or reproduction.

Female dugongs give birth every three to seven years. The typical pregnancy, which lasts for about one year, usually results in the birth of one calf; twins are rare. The female provides all care for the calf, and nurses, feeds with the mother’s milk, until eighteen months to two years of age. Georg Wilhelm Steller, a naturalist and physician who was responsible for the first recorded observations of the sea cow, reported seeing calves year-round, which suggests that mating occurred any time of year. According to Steller’s accounts, only single calves were born after a gestation period, pregnancy, of around one year, possibly longer.

DUGONGS, SEA COWS, AND PEOPLE

Steller’s sea cow was hunted to extinction within thirty years of its discovery. Dugongs have been hunted for their meat and other body parts, and increasingly are victims of boating and fishing accidents.

CONSERVATION STATUS

The sea cow is Extinct, no longer exists, and the dugong is Vulnerable, facing a high risk of extinction in the wild, primarily due to habitat destruction and human activities such as recreational boating and fishing. In 2004, the largest dugong population was located in Australia.