What do tuna eat
Cephalopoda - molluscs - molluscan - mollusks - octopuses, squid, and cuttlefish; and Nautiloidea.
Clupeoid - soft-finned fishes, small fish, herrings, sardines, menhaden, shad, salmon, and tarpon.
Arthropods - crustaceans - copepods - crabs, lobsters, crayfish, shrimp, krill and barnacles.
Planktonic - bacteria, archaea, algae, protozoa diatoms, jellyfish, and various larvae.
Tunicate - Ascidiacea, Thaliacea, Larvacea.
Algae - photosynthetic organisms - the red, green and brown algae.