Gammarids
Grayling, brown trout, and rainbow trout in varied water. The upper Isar above Sylvenstein is premier grayling water—clear and productive. Even urban sections hold fish.
- Limestone
Rules at a glance
- Licence required
Water temperature for Grayling
Ideal8°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 — water temperature is right today, though insect activity could be better. Grayling feeds actively in cold water — peak winter sport.
Likely species
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 5 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 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
Survey-backed · regionalHigh confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · November 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
2
1
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Grayling fly box
Southern Germany only. Trout and grayling in Bavarian meadow streams, alpine creeks and famous upper-river systems.
Hook 14–18 · Fly
in season
Permits & access
Permit required — see local rules.
- Upper Bavarian river
- Fischereischein + Erlaubnisschein required.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
Isar Terrain map
About this water
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
What this classification means
WFD ecological status Moderate → Good corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody DERW_DEBY_1_F402 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.
WFD classification · DERW_DEBY_1_F402
The full read · show the working · for Grayling · confidence 75%
How the 89 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow95 × 22%20.9
Clarity90 × 18%16.2
Feeding Time95 × 13%12.4
Pressure80 × 7%5.6
Insect activity46 × 12%5.5
Conditions total= 89
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
Directions
Seasons & zones
- Trout 1 March → 30 September
- Grayling 1 May → 31 December
Bavaria state rule: grayling (Äsche) closed 1 January – 30 April, minimum size 35 cm. Open season 1 May – 31 December. Individual fishery/Hegering may impose stricter rules or shorter access. Always check the specific permit (Fischereischein + Fischereiberechtigung). C&R recommended on classified trout/grayling waters.
Season dates are set at state or regional level — confirm the local rules.
Prime sport 1 August → 30 November
Related guides
Booking & contacts
Isar
Major Bavarian alpine river from the Karwendel mountains through Munich to the Danube.
Water temperature for Grayling
Ideal8°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 — water temperature is right today, though insect activity could be better. Grayling feeds actively in cold water — peak winter sport.
Likely species
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 5 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 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
Survey-backed · regionalHigh confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · November 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
2
1
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Grayling fly box
Southern Germany only. Trout and grayling in Bavarian meadow streams, alpine creeks and famous upper-river systems.
Hook 14–18 · Fly
in season
Permits & access
Permit required — see local rules.
- Upper Bavarian river
- Fischereischein + Erlaubnisschein required.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
Isar Terrain map
About this water
Grayling, brown trout, and rainbow trout in varied water. The upper Isar above Sylvenstein is premier grayling water—clear and productive. Even urban sections hold fish.
- Limestone
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
What this classification means
WFD ecological status Moderate → Good corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody DERW_DEBY_1_F402 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.
WFD classification · DERW_DEBY_1_F402
The full read · show the working · for Grayling · confidence 75%
How the 89 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow95 × 22%20.9
Clarity90 × 18%16.2
Feeding Time95 × 13%12.4
Pressure80 × 7%5.6
Insect activity46 × 12%5.5
Conditions total= 89
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
Directions
Seasons & zones
- Trout 1 March → 30 September
- Grayling 1 May → 31 December
Bavaria state rule: grayling (Äsche) closed 1 January – 30 April, minimum size 35 cm. Open season 1 May – 31 December. Individual fishery/Hegering may impose stricter rules or shorter access. Always check the specific permit (Fischereischein + Fischereiberechtigung). C&R recommended on classified trout/grayling waters.
Season dates are set at state or regional level — confirm the local rules.
Prime sport 1 August → 30 November
Related guides
Booking & contacts
At a glance
Isar is a freestone river in Bavaria / Munich, Germany. The catchment geology is recorded as limestone, and the water sits at about 683 m above sea level. The river is described as roughly 292 km long. Species listed for this water: brown trout, rainbow trout and grayling. The trout season is recorded as running from 1 March to 30 September. The grayling season is recorded as running from 1 May to 31 December. Best window recorded for anglers: April–September. Core methods listed: nymph; dry fly; streamer in lower sections. Level and flow data for this water is linked from 2 gauges. Its Water Framework Directive ecological status is recorded as good. Nearby waters in our listings include Walchensee at 39 km, Isar — guest-angler stretches at 39 km and Upper Ammer at 47 km.