Jung Joon-sung's Women and Harmony (356) Bluefin Tuna of the East Sea

'Tuna' is the English notation for tuna.

It derives from the ancient Greek 'thunnos'.

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

The name was given because their swimming speed can reach 70 to 90 kilometers per hour.

Growing up to a maximum body length of 4.2 meters and weight of 680 kilograms, this mackerel family fish is famous for its violent movements, as the name suggests.

The high hemoglobin content and the red color of their flesh are not unrelated to this.

They swim without stopping for a moment and breathe by opening their mouths and letting water flow through their gills.

This is a form of ram ventilation.

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

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

Conversely, when tuna die, this ATP converts to inosinate (IMP).

This is the reason for tuna's superior umami flavor.

Japan became the world's largest tuna consumer because of its attraction to this taste.

Before large-scale tuna aquaculture succeeded, tuna had no fixed habitat.

Classified as a pelagic migratory fish, they were caught abundantly in the temperate waters of the Pacific.

In spring and summer, they migrate northward through the East Sea to the Kuril Islands and Sakhalin, and move south in autumn.

Therefore, they have endothermic characteristics that maintain a constant body temperature.

This is the opposite of most fish, which are poikilothermic animals whose body temperature changes according to the surrounding water temperature.

Pacific bluefin tuna, a warm-water species of tuna, has been caught in large quantities off the East Sea coast for the past 6 to 7 years.

This is a result of climate anomalies with water temperatures rising more than 1 degree Celsius compared to 10 years ago.

The numbers tell a clearer story.

East Sea tuna catch, which was 25 tons in 2020, increased nearly 40-fold to 996 tons in 2024.

Excess Pacific bluefin tuna caught beyond the quota are often discarded.

Considering that Pacific bluefin tuna has high market value, this is unfortunate.

It is time to reconsider new fisheries policies to increase fishermen's income.