Manta rays feed on microscopic animals living in the water column called zooplankton.
Their mouths and gills are specially adapted to extract these tiny animals from the water via filtration. The cephalic lobes assist to funnel the plankton into their mouths.
They are often seen in numbers feeding near the surface in a current trail. In some parts of the world, mantas are seen feeding in a looping behaviour; doing repeated vertical loops with their mouth wide open.