Narwhals eat squid, Greenland hail-but, shrimp, Arctic cod, rock fish, flounder, and crab. Narwhals create a  sort of vacuum to suck up their prey. Narwhals are predators and preys. Narwhals have vestigial teeth. They have  two teeth which are vestigial. The male Narwhals  tusk is tusk less and also the females. Narwhals use their tusks to hunt. Narwhals use their horns to find mates. They use their horns also to fight rivals. Narwhals obtain water from the food they eat.