Salmon born in a Japanese river spend one to five years growing at sea, then find their way back to the exact river they hatched in to spawn — believed to navigate the open ocean using the sun and geomagnetic cues, then rely on smell alone for the final, precise leg home. Hokkaidō's Ishikari River is one of the most famous places to watch the run in person, thousands of fish crowding the shallows in a final push upstream.
The kanji don't quite match the fish, though. 鱖魚 (ketsugyo) properly names the mandarin fish, a Chinese perch that doesn't exist in Japan at all — the character combination was simply borrowed and reassigned to salmon, since both are river fish that gather in dense, visible schools. It's the same pattern this calendar keeps repeating: a name arrives from the continent attached to one thing, and gets quietly reassigned to whatever locally similar thing actually needed a name.
The season's namesake fish — this is peak run timing, and also when salted whole salmon (新巻鮭, aramaki-jake) starts appearing for New Year gifting and cooking.
At its true winter peak as 寒鰤 — the richest, most prized stretch of the entire buri season.
In full season; its scent is as central to this stretch of winter cooking as any single ingredient gets.
Late-season varieties keep well and stay reliably good through the cold months ahead.
At full sweetness, the anchor of winter nabe cooking.
Deep in season, excellent long-simmered in oden or added to a hot pot.
Still good, aromatic and slightly bitter against a rich broth.
Both remain the season's steady source of color, now fully established in New Year decorations and increasingly visible in shop-front and entryway arrangements as the month goes on.
Gutted, heavily salted, and traditionally wrapped in straw rope, aramaki-jake became a common oseibo gift by the late Edo period and remains one of the most recognizable. In Echigo's snow country it's known specifically as 歳取魚 (toshitori-zakana, "the fish that marks passing into the new year") — the centerpiece of the New Year's Eve meal, grilled, added to zōni soup, or rolled into kombu-maki. The salmon's return to its home river after years at sea made it an easy, resonant symbol for a New Year's meal built around homecoming and renewal.
"Returning home" — Ordinarily used for a person returning to their hometown or parents' house, and applied just as naturally to salmon completing the same kind of journey — back to a specific, remembered place rather than just anywhere familiar.
鱖魚 (ketsugyo) is a genuine Chinese word for the mandarin fish, a freshwater perch prized there as a delicacy — a species that simply doesn't occur in Japan. Whoever assigned this kō its name reused the character pair anyway, reading it as さけ (sake) rather than importing the fish itself, on the strength of a shared habit (river fish gathering in visible numbers) rather than any real taxonomic relationship.
The country's New Year's Eve 年取り魚 (toshitori-zakana, "year-taking fish") splits almost exactly along the Itoigawa-Shizuoka Tectonic Line: salmon east of it, buri (yellowtail) west of it, with a genuine mixed zone in Nagano — Nagano City favoring salmon, Matsumoto favoring buri, within the same prefecture. Aomori breaks the pattern further north still, favoring cod and cod roe instead of either.
Hokkaidō's Ishikari River is among the most famous viewing spots, but many regional rivers have a visible run around this kō worth a short trip to see.
Whether your household leans salmon or buri, both are in genuine peak season right now — a good week to secure a good one before New Year demand pushes prices up.
"The wide river doesn't hurry its current — and the salmon swim upstream regardless."
Whole salted salmon is often ordered ahead from a fishmonger for the New Year table — worth reserving now rather than hoping for a good one in the final week of December.
To arrive on New Year's Day itself, Japan Post generally asks that nengajō be posted by a mid-to-late December deadline — worth checking the current cutoff soon.
The river in this haiku isn't fighting the salmon or helping them — it's simply wide and unhurried, indifferent to the fact that something inside it is working as hard as it possibly can. Most effort happens in exactly that kind of neutral setting: no resistance dramatic enough to blame, no help dramatic enough to credit, just a current going its own unbothered pace while you do yours. What are you pushing against right now that isn't actually against you at all?