Mayflies
Stoneflies
Gammarids
- Ecology: Good
- Chemical: Unknown
WFD classification · SI21VT50
Rules at a glance
- Permit required
Water temperature for Grayling
Ideal13°C est.ideal 4–14°C
0°14°28°
How to fish it · for Grayling
When
Midday window — grayling feed best from late morning into early afternoon.
Where
Work runs and glides — grayling shoal in the bottom third of the water column.
Method
Tight-line nymph the bottom third with weighted patterns.
Kit
10 ft #3 rod, floating line, long leader to 4 lb fluoro for nymphs.
Why this works
Excellent — conditions well-balanced, with water temperature particularly in your favour.
Likely species
Hatch timeline · todayPeak at 14:00
12:00(now) — Reed Smut
Stage: On emergersApproach: Emerger or dryActivity: 59%
Also:Autumn Dun46%Cinnamon Sedge35%Heather Fly32%
Peak emergence window11 food groups active
Peak activity at 14:00 — Autumn Dun (Autumn Dun, 12 food groups active)
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 2 guilds as a supporter.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Supporters see what else is on the menu.
Start free trial14-day free trial. Cancel anytime.
Evidence
Records-basedModerate confidence
Based on species-occurrence records, not local invertebrate surveys.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
1
2
2
2
2
2
1
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Grayling
Permits & access
Permit required — see local rules.
- Fishing licence + permit
- Shared with Croatia.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
Canoe on the Kolpa Terrain map
Water quality (WFD)
The full read · show the working · for Grayling · confidence 90%
How the 84 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity71 × 12%8.5
Conditions total= 84
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Seasons & zones
- Trout 1 March → 30 September
- Grayling 16 May → 30 November
Slovenian common default: grayling 16 May – 30 November (lipan). Slovenia is permit and fishing district controlled — dates may vary by specific water. Always check the Ribiška Družina (fishing district) permit for the specific beat. The Soča, Idrijca, and Sava system hold world-class grayling alongside marble trout.
Prime sport 1 September → 30 November
- Hucho 1 October → 14 February
Related guides
Booking & contacts
River Kolpa
Water temperature for Grayling
Ideal13°C est.ideal 4–14°C
0°14°28°
How to fish it · for Grayling
When
Midday window — grayling feed best from late morning into early afternoon.
Where
Work runs and glides — grayling shoal in the bottom third of the water column.
Method
Tight-line nymph the bottom third with weighted patterns.
Kit
10 ft #3 rod, floating line, long leader to 4 lb fluoro for nymphs.
Why this works
Excellent — conditions well-balanced, with water temperature particularly in your favour.
Likely species
Hatch timeline · todayPeak at 14:00
12:00(now) — Reed Smut
Stage: On emergersApproach: Emerger or dryActivity: 59%
Also:Autumn Dun46%Cinnamon Sedge35%Heather Fly32%
Peak emergence window11 food groups active
Peak activity at 14:00 — Autumn Dun (Autumn Dun, 12 food groups active)
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 2 guilds as a supporter.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Supporters see what else is on the menu.
Start free trial14-day free trial. Cancel anytime.
Evidence
Records-basedModerate confidence
Based on species-occurrence records, not local invertebrate surveys.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
1
2
2
2
2
2
1
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Grayling
Permits & access
Permit required — see local rules.
- Fishing licence + permit
- Shared with Croatia.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
Canoe on the Kolpa Terrain map
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · SI21VT50
The full read · show the working · for Grayling · confidence 90%
How the 84 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity71 × 12%8.5
Conditions total= 84
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Seasons & zones
- Trout 1 March → 30 September
- Grayling 16 May → 30 November
Slovenian common default: grayling 16 May – 30 November (lipan). Slovenia is permit and fishing district controlled — dates may vary by specific water. Always check the Ribiška Družina (fishing district) permit for the specific beat. The Soča, Idrijca, and Sava system hold world-class grayling alongside marble trout.
Prime sport 1 September → 30 November
- Hucho 1 October → 14 February
Related guides
Booking & contacts