manatees are marine mammals that graze on sea grasses.They grow to 15 feet in length and can weigh up to 1500 pounds.Once they were found throughout the world's oceans.Today,however,manatees exist in limited number and only in certain tropical and subtropical waters.In Florida,the manateespopulation number only about 1900.Efforts by state and federal agencies and private organization to protect manatees have occurred for many years.