Manatees generally feed no deeper than 10 feet below the surface of the water. While resting, manatees can stay underwater for as long as twenty minutes, although they generally will average 2 or 3 minutes between breaths. The remainder of their time is spent traveling, curiously investigating objects and socializing by mouthing, rubbing against, and interacting with other manatees. Manatees in Florida feed on over 60 species of plants. These include turtle grass, manatee grass, shoal grass, mangrove leaves, various algae, water hyacinth and water hydrilla.
Manatees avoid specific plants such as splatterdock and waterpennywort that contain natural toxins.
Manatees feed off the bottom, in the water column and at the surface. They have even been know to crop overhanging branches, consume acorns and haul themselves partially out of the water to eat bank vegetation. Manatees use their front flippers and large flexible lips to manipulate vegetation. Horny ridged pads at the front of a manatee's palate and lower jaw break vegetation into small pieces. Behind these pads, molars grind the food.