Brown trout
- Brown trout live in fast flowing stony and gravelly rivers. In our chalk streams, they are usually golden brown in colour, with a dark back and creamy yellow belly. Black or red spots, sometimes with pale borders, are present on their back and sides. They are predatory fish, feeding on invertebrate larvae, small fish and flying insects, such as mayflies and damselflies. They are a sensitive sign of the health of the river and ecosystem.
- Spawning occurs between November and February, when the female digs a nest known as a ‘redd’ in the gravelly shallows by turning on her side and flexing her body to deflect the flow of the river down onto the bed. As she does this, the finer material is swept away downstream whilst the larger, coarser gravel settles back on the bed in a small mound. Now is the perfect time to spot these depressions and mounds of clean looking gravel in the river.
- Once the redd is cut, the female lays her eggs into the gravel mound and they are simultaneously fertilised by her selected male. The eggs are buried in the gravel and the young fish, known as alevins, hatch and feed on their nutritious yolk sac before moving on as free swimming “fry” to feed on invertebrates.
- Brown trout are here so try spot one when walking alongside the river. Please look for both brown trout and their redds only from the bank. It is important to be very careful not to enter the water or allow dogs to do so during the crucial breeding season. The redds are not always obvious. They are easily destroyed or disturbed so the fish’s precious energy spent in building the redd is wasted and their year’s spawning effort is lost.