Fish · GBIF taxon 5203999
European Grayling
Thymallus thymallusAlso known as Grayling, Harjus, Lady of the Stream
European grayling thrive in clean, cool, oxygen-rich rivers, easily recognized by their iridescent scales and prominent, sail-like dorsal fin patterned with red and violet spots. During spring spawning, males display this high dorsal fin in territorial rituals to attract females and claim prime gravel runs. Highly sensitive to aquatic pollution and thermal stress, these elegant fish serve as vital ecological barometers for health across Eurasian river networks.
FreshwaterIndicator SpeciesColdwater
Licensed referenceZsoldos Márton / CC BY-SA 3.0 · cc-by-sa
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Diet & prey
- Mayfly Nymphs
- Caddisfly Larvae
- Gammarus Amphipods
Predators
- Eurasian Otter
- Grey Heron
- Northern Pike
ThreatsWater pollution, thermal stress from climate change, and river impoundments
HabitatsFast-flowing cold rivers, clean upland streams, and subalpine lakes
Life span10–15 years
Size / weightNot available
Classification
- FamilySalmonidae
- SpeciesThymallus thymallus
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe from stream banks or while wade fishing.
- What to notice
- Look for a slender silver fish with a tall, colorful sail-like dorsal fin in clear river currents.
- Support conservation
- Avoid wading near gravel spawning beds during spring and minimize handling during summer heat waves.
Responsible observation
- Polarized Lenses: Wear polarized sunglasses to spot grayling holding position over gravel in clear streams.
- Minimal Handling: Use barbless hooks and wet hands if practicing catch and release fishing.
- Spawning Respect: Avoid wading through gravel beds during spring to protect delicate eggs.
Co-occurring Competitor (c) kirk gardner, some rights reserved (CC BY), uploaded by kirk gardner · cc-by
Co-occurring Species (c) Emőke Dénes, some rights reserved (CC BY-SA) · cc-by-sa
Close Relative (c) Bruce Deagle, some rights reserved (CC BY), uploaded by Bruce Deagle · cc-by
Co-occurring Relative (c) nicolás, some rights reserved (CC BY-SA) · cc-by-sa
Help improve the field guideSomething wrong?
Checking your Fauna account…Report a name, category, or profile issue for review.