Description and characteristics
The trout (Salmo sp.) is a medium-to-large salmonid with a fusiform body covered with small scales. Colouring varies from silvery to brown-green, with black and reddish spots on the flanks. It has the adipose fin characteristic of salmonids.
Habitat and distribution
It prefers clear, cold, oxygen-rich waters with fast currents and stony bottoms — Danube branches and mountain tributaries. It is sensitive to water quality.
Diet and behaviour
It is an active predator, feeding on insects, larvae, crustaceans, worms and small fish. It frequently hunts at the surface, being prized in fly fishing.
Reproduction
Spawning occurs in cold waters in autumn or winter, with females laying eggs on stony bottoms in mountain waters. The fry are pelagic, then move to the bottom.
Economic and ecological importance
The trout has great economic and sport value, being also farmed in aquaculture. Ecologically, it is an indicator of the quality of clear waters.
Threats and conservation
It is affected by pollution, dams, water warming and overfishing. Protection of cold, clear waters is essential.
Fishing and legal minimum size
The trout is fished for sport, with a fly or natural baits. In the table of minimum legal sizes, the trout (Salmo sp.) has a minimum legal size of 20 cm.
Conclusion
The trout is an emblematic salmonid, a symbol of clear, cold waters, important for biodiversity and fishing.