Jung Jun-sung's Yeomindongnak (356) Bluefin Tuna from the East Sea

'Tuna' is the English term for tuna.

It derives from the ancient Greek word 'tunos'.

It means 'to move quickly' or 'to fly away'.

It was named after the fish's swimming speed, which can reach 70 to 90 kilometers per hour.

Belonging to the mackerel family, it grows to a maximum body length of 4.2 meters and weighs up to 680 kilograms, and is famous for its violent movements, as the name suggests.

Its high hemoglobin content and the resulting reddish color of its flesh are also related to this.

It swims without stopping for even a moment, breathing by opening its mouth and allowing water to flow over its gills.

This is a type of ram ventilation breathing.

This is why they die immediately when removed from the water.

As a result, tuna accumulates large amounts of adenosine triphosphate (ATP) in its body.

When tuna dies, however, this ATP is converted to inosinate (IMP).

This is the reason for tuna's excellent umami taste.

Japan became the world's largest tuna consumer partly due to its fascination with this flavor.

Before large-scale tuna farming was successful, tuna had no fixed habitat.

Classified as a migratory pelagic fish, it was caught abundantly in the temperate waters of the Pacific Ocean.

In spring and summer, it migrates northward through the East Sea to the Kuril Islands and Sakhalin, and moves southward in autumn.

Therefore, it possesses homeothermic characteristics, maintaining a constant body temperature.

This contrasts with most fish, which are poikilothermic animals whose body temperature changes with the surrounding water temperature.

Bluefin tuna, a type of warm-water fish species, has been caught in large quantities off the East Coast since six to seven years ago.

This is a consequence of climate change, as water temperatures have risen more than 1 degree Celsius compared to a decade ago.

The numbers are even more striking.

The catch of tuna species off the East Coast, which was 25 tons in 2020, increased nearly 40-fold to 996 tons in 2024.

It is common for bluefin tuna caught beyond the quota to be discarded.

Given that bluefin tuna holds high market value, this is unfortunate.

It is time to consider new fisheries policies to increase fishermen's incomes.