Asahi Shimbun reporters dive into a set net off the town of Rausu on the eastern side of Hokkaido’s Shiretoko Peninsula. The early October dive coincided with the peak time for set net salmon fishing.

Photo/Illutration A shoal of pointhead flounder inside a set net off Rausu, Hokkaido, on Oct. 6 (Takuya Isayama)

RAUSU, Hokkaido—Set net fishing for salmon, where nets are dropped along migrating fish routes, is at its seasonal peak off the Shiretoko Peninsula on the eastern point of Japan’s northernmost main island.

Asahi Shimbun reporters dove into one set net in early October off the coast of the town of Rausu.

Within the net, divers saw shoals of salmon, fully grown after several years on the high seas.

A recent fishery catch report says 352,313 heads of salmon were caught in Rausu as of the end of September—a booming 80 percent more than 2023’s haul

Catches, however, remain poor in many areas, and the total catch from all regions of Hokkaido is down about 20 percent on average from last year, sources said.

Apart from salmon, fish of various species were also seen inside the set net on the day of the reporters’ dive.

Mackerel and mottled skate, a ray species typically boiled, accounted for many of them.

Pointhead flounder, a flatfish species usually enjoyed dried, were also seen closely crammed together at the bottom of the net.

“You sometimes even see sunfish and mahi-mahi inside set nets,” said Katsunori Seki, head of Shiretoko Diving Co. “The charm of set net diving is that you can encounter fish migrating offshore.”