Caddisflies
Damselflies & dragonflies
Gammarids
- Ecology: Good
- Chemical: Unknown
WFD classification · HRCSRN0012_004
Rules at a glance
- Permit required
Water temperature for Grayling
Ideal12°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
Caddisflies
- Green SedgeMost likelyLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
- Net-spinning caddisAlso possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
Damselflies & dragonflies
Hatch timeline · todayPeak at 18:00
12:00(now) — Autumn Olive
Stage: On emergersApproach: Emerger or dryActivity: 55%
Also:Brown Sedge47%Daddy Long Legs35%Autumn Needle Fly32%
Peak emergence window10 food groups active
Peak activity at 18:00 — Large Cinnamon Sedge (Large Cinnamon Sedge, Weather boost)
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
Top prey shown — see all 4 as a supporter.
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
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Brown SedgeHatch
2
3
3
3
2
Small SpurwingHatch
2
3
3
3
2
Small Dark OliveHatch
2
3
3
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Grayling
Hook 14–18 · Fly
in season · matches water height
Permits & access
Permit required — see local rules.
- Croatian fishing licence + local permit.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
Mrežnica Terrain map
Water quality (WFD)
The full read · show the working · for Grayling · confidence 90%
How the 86 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity77 × 12%9.2
Conditions total= 86
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Seasons & zones
- Trout 1 March → 30 September
- Grayling 16 May → 30 November
Croatian rules: artificial fly or lure only in permanent grayling habitats. Check concession rules for the specific water.
Prime sport 1 September → 30 November
- 16 May → 30 Nov · Artificial fly or artificial lure
Related guides
Booking & contacts
Mrežnica
Water temperature for Grayling
Ideal12°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
Caddisflies
- Green SedgeMost likelyLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
- Net-spinning caddisAlso possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
Damselflies & dragonflies
Hatch timeline · todayPeak at 18:00
12:00(now) — Autumn Olive
Stage: On emergersApproach: Emerger or dryActivity: 55%
Also:Brown Sedge47%Daddy Long Legs35%Autumn Needle Fly32%
Peak emergence window10 food groups active
Peak activity at 18:00 — Large Cinnamon Sedge (Large Cinnamon Sedge, Weather boost)
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
Top prey shown — see all 4 as a supporter.
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
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Brown SedgeHatch
2
3
3
3
2
Small SpurwingHatch
2
3
3
3
2
Small Dark OliveHatch
2
3
3
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Grayling
Hook 14–18 · Fly
in season · matches water height
Permits & access
Permit required — see local rules.
- Croatian fishing licence + local permit.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
Mrežnica Terrain map
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · HRCSRN0012_004
The full read · show the working · for Grayling · confidence 90%
How the 86 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity77 × 12%9.2
Conditions total= 86
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Seasons & zones
- Trout 1 March → 30 September
- Grayling 16 May → 30 November
Croatian rules: artificial fly or lure only in permanent grayling habitats. Check concession rules for the specific water.
Prime sport 1 September → 30 November
- 16 May → 30 Nov · Artificial fly or artificial lure
Related guides
Booking & contacts