They are able to move freely between salinity extremes. Manatees migrate into warmer waters when the water temperature drops below 68 degrees. Manatees average about 10 feet in length. Large individuals may reach lengths of up to 13 feet. Average adult weights are approximately 800 to 1200 pounds, with big individuals weighing up to 3500 pounds.
Female manatees are generally larger than the males.
All manatees have sparse hair scattered over their bodies. The manatee is streamlined, full around the middle and narrowing to a paddle shaped tail. Manatees are usually grayish brown. Organisms such as algae may grow on these slow moving creatures, helping to determine their coloration. Manatees generally feed no deeper than 10 feet below the surface of the water.