All sirenians are herbivores.
They feed on a wide variety of submerged, emergent, floating, and shoreline vegetation. 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. All manatees eat vegetation. Manatees avoid specific plants, such as spatterdock and waterpennywort, that contain natural toxins.