Rules at a glance
- Public water
- Licence required
Water temperature for Brown Trout
Warm — slow18.2°Cideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Water at 18.2°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots.
Hatch timeline · todayPeak at 11h
Hatch predictions
Today's headline hatch shown — see all 3 active hatches hour by hour as a supporter.
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 · October highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
1
March BrownHatch
2
3
2
Late March BrownHatch
2
3
2
Large Brook DunHatch
2
3
2
Large StoneflyHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Brown Trout
Permits & access
Permit required — see local rules.
- Basque fishing licence required
- Salmon fishing is banned on all Bizkaia rivers
- The upper Artibai (Iruzubieta bridge to the Otola industrial estate) is closed; below the Andonegui dam is coarse water where trout must be returned
- Check the current Diputación Foral de Bizkaia order.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 1
Water here at 18.2°C — the fishing's alive, but these are cooler if you'd rather rest the warm water.
Gallery · 2
Terrain map
The full read · show the working · for Brown Trout · confidence 80%
How the 39 is built — score × weight = contribution
Temperature38 × 28%10.6
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity31 × 12%3.7
Conditions total= 65
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
- Trout premier Sunday de April → 31 July
Salmon: Heritage only (2026) — No functioning salmon run, and Bizkaia bans salmon fishing on all its rivers (Orden Foral 2084/2026). Fish it for trout.
Related guides
Booking & contacts
Río Artibai
Water temperature for Brown Trout
Warm — slow18.2°Cideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Water at 18.2°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots.
Hatch timeline · todayPeak at 11h
Hatch predictions
Today's headline hatch shown — see all 3 active hatches hour by hour as a supporter.
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 · October highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
1
March BrownHatch
2
3
2
Late March BrownHatch
2
3
2
Large Brook DunHatch
2
3
2
Large StoneflyHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Brown Trout
Permits & access
Permit required — see local rules.
- Basque fishing licence required
- Salmon fishing is banned on all Bizkaia rivers
- The upper Artibai (Iruzubieta bridge to the Otola industrial estate) is closed; below the Andonegui dam is coarse water where trout must be returned
- Check the current Diputación Foral de Bizkaia order.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 1
Water here at 18.2°C — the fishing's alive, but these are cooler if you'd rather rest the warm water.
Gallery · 2
Terrain map
The full read · show the working · for Brown Trout · confidence 80%
How the 39 is built — score × weight = contribution
Temperature38 × 28%10.6
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity31 × 12%3.7
Conditions total= 65
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
- Trout premier Sunday de April → 31 July
Salmon: Heritage only (2026) — No functioning salmon run, and Bizkaia bans salmon fishing on all its rivers (Orden Foral 2084/2026). Fish it for trout.
Related guides
Booking & contacts