River fish populations in a Suffolk beauty spot have seen an upturn. A three yearly survey carried out by the Environment Agency in East Anglia looked at fish numbers and species along the River Stour at Dedham. Apart from 2021 - when the survey was not carried out due to the Covid pandemic - the team recorded their best results for fish numbers in recent years.
The number of species equalled the highest - suggesting the fish population in the river has improved. Surveys carried out 2015 and 2018 had fewer individual fish and fewer species than in 2024. The team on the River Stour caught 15 species and more than 600 fish including eel, chub, roach, bleak, dace, tench, pike, bullhead, spined loach, gudgeon, perch and flounder.
At the end of the survey all of the fish get returned to the river and the nets are removed. Fish being counted and measured (Image: Environment Agency) Dan Hayter - who monitors fish in rivers for the Environment Agency - said the survey was carried out using "electric fishing" - which involves passing a mild electrical field through the water to temporarily immobilise the fish to allow the team to catch them. "To conduct a fish survey, we measure out a 100-metre stretch of the river and place a large stop net at the start and end of the stretch to prevent fish moving in and out during the survey," he said.
"Four of us then get in a motorised boat and travel along the stretch with specialised electric fishing equipment. "We usually have one person manoe.