When they're completely grown, manatees weigh 800 to 1,200 pounds (360-545 kilograms) and access ten ft (3 meters) in duration. The greatest of the species can mature to be up to 3,500 pounds (1,590 kilograms) and 13 ft (4 meters) in length. Their hard skin is wrinkled, and their size is no joke: They're about four to 4.5 toes (1.2 to 1.4 meters) lengthy at delivery and typical 60-70 kilos (27 to 32 kilograms). Friends die.