Freestone · Limestone Influenced · Shikoku

Niyodo River

Niyodo River in Ino town, Kochi pref Japan

The Niyodo is famous for a colour — 'Niyodo blue', the luminous clarity that limestone gives its water — and runs through the green mountains of Kōchi as one of the most beautiful rivers in Japan, holding amago and iwana in pools you can see straight to the bottom of.

Poor · Amago
Tenkara kebari (reverse-hackle) · 12–16
Poorlive now
Not the day for it
Low and clear — careful approach country. A morning for the obvious fish only.
90% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp22.8°C
  • ClarityClear
Today's fly
TK
Tenkara kebari (reverse-hackle)12–16
A dependable searching pattern for these waters.
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp22.8°C
ClarityClear
Weather30°C
WindNW 8 km/h
Pressure1013 hPa
Rain · recent0.0 mm
Rain · ahead0.8 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for Amago
Warm — slow
23°C est.ideal 9–17°C
0°14°28°
How to fish it · for Amago
When
March/April to the autumn closure
Where
The Niyodo is famous for a colour — 'Niyodo blue', the luminous clarity that limestone gives its water — and runs through the green mountains of Kōchi as one…
Why this works
Water at 22.8°C. This is the line where catch-and-release kills masu salmon. Do not fish for them today.
Hatch timeline · todayPeak at 6pm

Hatch predictions

Today's headline hatch shown — see all 2 active hatches hour by hour with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 3 with Pro.

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Evidence
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water yet.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Stenopsyche CaddisHatch
2
3
3
2
Cicada (Semi)Hatch
2
2
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Amago fly box
EH
Elk Hair / Stenopsyche caddis
12–14 · Sedge
Evening sedge — twitch or dead-drift it as the light goes.
CB
Cicada & beetle terrestrials (midsummer)
10–12 · Terrestrial
Fish it tight to the bank on warm, breezy days.
Permits & access
Permit required — see local rules.
  • Co-operative yugyoken required; spawning closure in autumn
  • Confirm reach and method rules.
What's coming
Plan ahead
5-day outlook
Water here around 23°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. Niyodo River in Ino town, Kochi pref Japan
    Clear water river in Shikoku.
  2. Terrain map of the venue
    Terrain map
About this water

The Niyodo is famous for a colour — 'Niyodo blue', the luminous clarity that limestone gives its water — and runs through the green mountains of Kōchi as one of the most beautiful rivers in Japan, holding amago and iwana in pools you can see straight to the bottom of. Sight-fishing water in a landscape of gorges and clear pools.

Under the surface

A river celebrated for its luminous limestone-blue clarity, running through the green Kōchi mountains of Shikoku. Amago and iwana hold in pools so clear they seem bottomless; this is sight-fishing water, gorge and pool and astonishing colour.

Wading: Gin clear water, slick bedrock — stealth essential

  • River
  • Limestone influenced
  • Confined
  • Pool riffle
  • Pocket water
Conservation note

White-spotted char (iwana) and amago — the prized Shikoku red-spotted native.

The full read · show the working · for Amago · confidence 90%
How the 6 is built — score × weight = contribution
Temperature3 × 28%0.8
Flow45 × 22%9.9
Clarity95 × 18%17.1
Feeding Time55 × 13%7.2
Pressure80 × 7%5.6
Insect activity52 × 12%6.2
Limiting factor: Water temperature (22.8°C) is outside Amago's preferred range (9–17°C)= 47
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 9–17 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Char late February to April → late September to mid-October

    Honshu/Shikoku/Kyushu keiryu are managed by local fishery co-operatives — a yugyoken (day/annual ticket) is required, and most streams close around 30 September / mid-October for spawning. Species are surfaced in prose only (no engine slugs for yamame, amago or iwana). Legal status: guidance_not_permission.

Related guides
Euro Nymphingsubsurface methods
Booking & contacts