Language English Adult brook trout Photo: Biodôme Adult brook trout Photo: Biodôme Adult brook trout Photo: Biodôme OngletsDescriptionDistinguishing featuresThe colouring of the brook trout's marbled markings varies with age and environment. The back varies from olive green to black. The flanks are marked with pale spots and red spots with blue halos. The male has a long, hook-shaped lower jaw and is larger than the female. ReproductionThese fish reach sexual maturity at two to three years. They usually spawn in autumn, in shallow running water. The females produce between 100 and 5,000 eggs, depending on size. DietBrook trout eat a wide variety of invertebrates: aquatic insect larva, terrestrial insects, spiders, worms, leeches and molluscs. They also eat fish eggs, fish and sometimes mammals, amphibians and reptiles. Their diet shifts to fish as they age. PredatorsThe enemies of the adult are other fish and humans. The eggs and young are eaten by birds and certain species of fish. HabitatBrook trout live in clear and well-oxygenated freshwater streams, rivers and lakes, at temperatures below 20°C. Ecology, behaviourDeforestation and pollution have resulted in physical and chemical degradation of their habitat and significant declines in certain stocks. Since 1984, only sport fishing of the species has been allowed. Better control of catches and stocking of certain lakes could slow their decline. French nameOmble de fontaine Scientific nameSalvelinus fontinalisPhylumChordataClassOsteichthyes (bony fish)OrderSalmoniformesFamilySalmonidaeSizeTotal length: 25 to 50 cmWeight0.5 to 1.5 kgLife span5 to 6 yearsStatusIndéterminé; fished for sport.