Tuna, as an apex predator in the marine ecosystem, has dietary habits that are closely linked to its living environment and physiological characteristics.

The vast expanse of the ocean provides tuna with a rich and varied food source. Small fish such as sardines and herring, with their rich protein and fat content, become the main energy supply station for tuna. Crustaceans such as shrimps, crabs and krill also occupy a share of the tuna's diet, especially krill, which is abundant and easily accessible, and is a key nutrient for the growth of young tuna. Cephalopods such as squid and octopus, with their wide distribution and abundant nutrients, overlap with the tuna's habitat and become one of its daily feeding targets.

In order to efficiently obtain this food, the tuna has evolved a unique way of feeding. Its streamlined body gives it the ability to swim quickly in open waters, accelerating instantly into schools of small fish such as schools of sardines to kill its prey with precision. In addition, the tuna also understands the power of group cooperation, they often act collectively, the prey surrounded to a small area, and then take turns to rush into the prey, greatly improving the efficiency of predation. When food is scarce, tuna also show a flexible survival strategy - filter feeding. They open their mouths wide and allow seawater to carry plankton and small organisms through their gill rakers, thus satisfying their own survival needs.

Tuna's unique dietary habits are not only its survival wisdom to adapt to the marine environment, but also a vivid reflection of the biodiversity and complexity of the marine ecosystem.