SHIZUOKA, Sep 05 (News On Japan) - The Japan Meteorological Agency has announced the end of the longest-ever Kuroshio meander, which lasted seven years and nine months. The shift in the current, blamed for poor catches of marine products, has finally subsided, but concerns remain over its aftereffects and the possibility of recurrence.
In a seaside warehouse in Minami-Izu, Shizuoka Prefecture, lobster nets were neatly stacked, waiting for the fishing season to begin. The town’s lobster fishing season opens in mid-September, but in recent years, catches have been poor. The cause has been attributed to the Kuroshio meander.
The phenomenon occurs when the Kuroshio Current, which normally flows south of Honshu, is diverted by the formation of cold-water eddies. As a result, spiny lobster numbers off Minami-Izu are believed to have declined.
The Kuroshio meander began in August 2017 and, according to the Meteorological Agency, ended in April 2025.
Lobster fisherman Satoshi Tani said, “If seaweed increases, then shellfish and shrimp that feed on it will also increase, and hopefully the ocean will become rich again, like it was about ten years ago.”
The impact was also felt by fishmongers. At Hinode, a long-established fish shop in Shizuoka City’s Aoi Ward, owner Shingo Kawase said the range and volume of fish arriving changed significantly since the meander began. “Alfonsino have been declining dramatically for the past seven to eight years. Even when available, prices have risen and good-quality fish have become scarce,” Kawase explained.
But this season has brought encouraging signs for another species long hit by poor catches. “This year, sanma are huge,” said Kawase. “Some weigh 200 grams each, sizes we haven’t seen in four or five years.”
Although the meander has ended, the drastically altered marine environment is unlikely to recover quickly. Experts warn of lingering effects.
Toru Miyama, senior researcher at the Japan Agency for Marine-Earth Science and Technology, noted, “Even though the Kuroshio meander has subsided, global warming has continued over the past eight years. The ocean has not returned to its previous state, and temperatures remain elevated.”
The rise in sea temperatures and damage from the meander mean marine ecosystems cannot be expected to recover immediately. Whether fishing grounds and catches will return to their former levels is uncertain. Moreover, there is still a possibility of the meander returning.
Miyama cautioned, “This time the meander ended when its eddy was expelled, but that eddy has already reattached near Wakayama Prefecture. If it grows, the Kuroshio meander will recur. The next two months are crucial.”
Source: SBSnews6
