Freestone · Limestone Influenced · Shikoku, JP

Niyodo River

Niyodo River in Ino town, Kochi pref Japan
Tomorrow · A proper day on the water
Sculpin Streamer
Forecast · Tomorrow
A proper day on the water
A proper day for it. Work the seams with an upstream nymph, switch to the dry when they show.
90% projected
Today's fly
Sculpin Streamer
Sculpin Streamer
Conditions on the water · Tomorrow
Estimate
Level
Moderate rain recently
No gauge reading
Water temp10.5°C
ClarityClear
Weather16°C
WindN 20 km/h
Pressure1015 hPa
Rain · recent22.0 mm
Rain · ahead0.0 mm

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

Water temperature for White-spotted Char
Ideal
11°C est.ideal 7–14°C
0°14°28°
How to fish it · for White-spotted Char
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
Poor — water temperature is working for you, but water clarity is the limiting factor today.
Hatch timeline · tomorrowPeak at 6h

12h(now) — Autumn Olive

Stage: On emergersApproach: Emerger or dryActivity: 52%
Also:Black Gnat49%Autumn Needle Fly44%
Peak emergence windowWeather boost10 food groups active

Peak activity at 6h — Kajika Sculpin (Japan) (Kajika Sculpin (Japan), Weather boost)

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds as a supporter.

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Supporters see what else is on the menu.

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Evidence
Records-basedModerate confidence

Based on species-occurrence records, not local invertebrate surveys.

Through the year
0–3 scale · October highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Stenopsyche CaddisHatch
2
3
3
2
Cicada (Semi)Hatch
2
2
Ephemera strigata (Mid-Reach Keiryu Mayfly)Hatch
2
3
3
3
2
Epeorus latifolium (Riffle Mayfly)Hatch
2
3
3
3
3
3
2

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

Ranked for today
Fly box · White-spotted Char
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
Fishing better nearby · 2
Shimanto River
50 km
79
White spotted char · Amago
Yoshino River (upper / Ōboke)
56 km
30
White spotted char · Amago
Gallery · 2
  1. Niyodo River in Ino town, Kochi pref Japan
    Clear water river in Shikoku.
  2. Terrain map of the venue
    Terrain map
Conservation note

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

The full read · show the working · for White-spotted Char · confidence 45%
How the 30 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow60 × 22%13.2
Clarity15 × 18%2.7
Feeding Time70 × 13%9.1
Pressure75 × 7%5.3
Insect activity64 × 12%7.7
Limiting factor: Water is very coloured — too coloured for White-spotted Char= 66
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
A drop and clear would lift the flow and clarity scores.
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