Tuna are predatory fish. That is, they hunt other fish to feed themselves. In the case of tuna, these include primarily herring, mackerel, and crustaceans. Because of their size, they have few predators. These are mainly swordfish, certain whales, and sharks.
Tuna live in the sea. They can be found in almost all climatic zones, except in the polar region. The name tuna comes from the language of the ancient Greeks: the word “thyno” means something like “I hurry, the storm”. This refers to the fast movements of the fish.
Tuna can reach body lengths of up to two and a half meters. As a rule, tuna weigh more than 20 kilograms, some even over 100 kilograms. But these are particularly large specimens. Tuna have a gray-silver or blue-silver body. Their scales are rather small and only visible up close. From a distance, it looks like they have smooth skin. A special feature of the tuna is their spikes on the back and belly. The caudal fins of tuna are sickle-shaped.
Tuna are among the most important food for fish. Their flesh is red and fatty. Most tuna are caught in Japan, the United States, and South Korea. Some species of tuna, such as bluefin tuna or southern bluefin tuna, are critically endangered because humans catch too many of them.
Pots are used to catch the tuna. These are nets that they can swim into but not out of. In Japan and other countries, there are also large driftnets that the ships pull behind them. This is forbidden because so many dolphins and sharks are caught that should actually be protected. So that this doesn’t happen and the tuna are overfished in certain parts of the sea, there are now prints on cans that are supposed to prove sustainability.