Adaptations for Survival
Swimming - While manatees may not be the quickest of swimmers, they are actually quite agile and maneuver rather well considering their size. Propelled by they're large round flukes, manatees have been clocked up to 15 mph. Generally cruising manatees swim at approximately 2 - 6 mph. Because of their immense size, manatees have no natural predators other than man, so they have no real need to be fast swimmers.
Respiration - Research shows that manatees renew up to 90% of the air in their lungs in a single breath. (Humans renew only about 10%) Manatees can hold their breath for approximately 20 minutes, but on average manatees go to the surface for air every to to three minutes. Smaller more active manatees would probably surface more often.
Manatees taking a quick breath
Feeding - Manatees are herbivores which means they eat only plants. Their diet consists of over 60 species of plants which include turtle grass, manatee grass, shoal grass, mangrove leaves, water hyacinth, and water hydrilla. Not only do manatees eat aquatic plants, but they also feed on algae and the crustacea such as barnacles which may grow on these plants.
Turtle grass and a manatee eating water hydrilla