Sea World, San Diego recently opened an exhibit called Manatee Rescue which allows guests to view manatees in a semi-natural environment. Click here for other manatee news. Dugongs can reach up to three meters long and weigh up to 400 kilograms. Dugongs spend their entire lives at sea, usually in shallow waters to protect themselves from large waves and storms. They never come on land and only rise to the surface to breathe.
Dugongs are very vulnerable to predators because they are very slow-moving.
Their natural predators are large sharks, saltwater crocodiles, and killer whales. Threat to Manatees and Dugongs Manatees Warm water is necessary to the survival of the manatees. If they remain in the cold waters of the Gulf of Mexico, they are susceptible to a respiratory illness, which is the most common natural cause of death for manatees. This is not the leading cause of death, however. More than 90 percent of manatee mortalities are due to collisions with speedboats.