Shinshu salmon

Nagano has no coastline, yet its hotels and inns wanted a regional fish to place before visitors. The prefecture already had a rainbow trout base, with large-scale production beginning around 1950. As eating habits shifted and sashimi and sushi became more important, the fisheries station looked toward a fish suited to raw preparations and aquaculture.

The name Shinshu Salmon points to salmon color, while the fish's roots sit in Nagano trout farming. A silver body, red flesh, fine texture compared with rainbow trout, and thick meat gave inns, hotels, and restaurants a concrete way to serve a Nagano fish at the table.

The parentage is exact: female tetraploid rainbow trout crossed with male brown trout. The pairing creates a triploid aquaculture fish without reproductive ability, so each generation is produced for farming through managed broodstock and seed fish at the fisheries station.

This method also fits existing farms. Rainbow trout facilities and techniques can be used, and the fish is stronger against diseases that rainbow trout are prone to. The result keeps the visible traits that define the table experience: silver skin, red flesh, and meat that is fine and thick.

Development began in 1994 and ran for about ten years. The demanding step was making tetraploid rainbow trout. Over that period, about 220,000 fertilized eggs were pressure-treated, and 43 tetraploid rainbow trout were produced.

Those numbers give the fish a tactile timeline. Year after year, fertilized eggs had to be treated, a broodstock group had to grow large enough to provide eggs, and the triploid fish had to move from breeding work into Nagano aquaculture.

Shinshu Salmon does not produce eggs, so nutrients are not drawn into spawning. Its flesh stays consistently good to eat, thick, fine-textured, and rich in flavor; those qualities match the original aim of a fish for sashimi and sushi.

From fry, it takes roughly two years to reach about 50 to 60 centimeters and 1.5 to 2 kilograms. That body size and meat thickness give the red flesh a clear presence on the plate. On Nagano tables, the fish appears as a farmed trout with salmon-like color.

Production then moves from the fisheries station into the prefecture. The station produces seed fish and supplies fry to Nagano aquaculture operators. The promotion council noted the start of fry shipments in both 2023 and 2024, and it announced a fish-farming seminar with fisheries station staff as instructors.

The cooperative side shows another step after farming. The Nagano Prefecture Aquaculture Cooperative includes Shinshu Salmon among the fish it handles and describes smoked preparations made from fish raised by cooperative members and finished by makers in different parts of Nagano. Tanks, fry shipments, farms, and processing hands all sit inside the same prefectural flow.

In 2024, the promotion council pointed to twenty years of Shinshu Salmon through development work, aquaculture operators, and restaurants. That milestone places the fish beyond its first breeding stage and inside production and dining scenes in Nagano.

What lasts around Shinshu Salmon is visible in specific work: inns asking for a regional fish, the fisheries station managing broodstock and seed fish, farmers receiving fry, restaurants handling red trout flesh, and makers smoking fish raised by cooperative members. Its place in Nagano is built through tanks, shipments, farming skill, and plates set for guests.