trout


The trout, a popular freshwater fish and a popular sport fish, lives in clear, cool rivers and lakes. This fact sheet provides concise information on size, weight, lifestyle, and reproduction, and highlights the importance of protecting healthy waters for trout populations.

trout Products

Profile: trout

  • Scientific classification

    • Class: Bony fishes (Actinopterygii)
    • Order: Salmoniformes
    • Family: Salmonidae
    • Genus: Salmo / Oncorhynchus
    • Species: S. trutta (brown trout), O. mykiss (rainbow trout)

  • Physical characteristics

    • Size: 20–60 cm, rainbow trout usually 30–60 cm
    • Weight: 0.2–3 kg, in exceptional cases up to 5 kg
    • Special features: Streamlined body, spotted scale pattern, silvery to greenish-brown plumage, strong tail fin, very agile swimmers

  • Habitat and distribution

    • Common regions: Europe, North America, Asia
    • Habitat: Flowing waters such as streams and rivers, lakes with cool, oxygen-rich water; prefers clear, rocky waters with currents

  • Nutrition

    • Diet: Carnivore
    • Typical food: insects, larvae, small crustaceans, small fish and fish eggs

  • Reproduction and lifestyle

    • Spawning season: autumn to winter (depending on region and species)
    • Eggs: 2,000-5,000 eggs per female
    • Lifestyle: Territorial, solitary except for spawning season; very agile and fast swimmers, sometimes migrating upstream for reproduction

  • Lifespan and protection status

    • Life expectancy: 4–8 years, brown trout can live up to 10 years
    • Threat status: Partially threatened by water pollution, overfishing and habitat changes
    • Protective measures: protection and renaturation of rivers and streams, stocking measures in fish-poor waters, water protection