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Thames Brown Trout kept in The Loop

We have found evidence that brown trout are spawning in the River Thames for the first time in more than 20 years.

Juvenile brown trout were discovered by fisheries officers near Eynsham in Oxfordshire during an investigative fish survey on the River Thames. The trout were found in a habitat that we restored in 2007.

The presence of juvenile trout is an extremely positive sign for the River Thames, and is the first indication of successful spawning in the main river in surveys dating back over 20 years.

Fisheries Officer Lizzie Rhymes said: “Brown trout are very sensitive to the amount of oxygen in the water, and to the concentration of pollutants. To spawn successfully they require a clean gravel river bed, free from silt deposits. The discovery of brown trout in this area is a brilliant result for the river, indicating the presence of good quality habitat.”

In partnership with Oxfordshire County Council and the Wychwood Project, we restored the 300m section of river known as the Eynsham Loop. The GBP13,000 project, funded largely by the sales of anglers’ rod licences, improved habitat for fish and other wildlife by recreating natural features which had been lost in the river during historical dredging of the channel.

Limestone rocks and gravel were put into the river channel to raise the river bed in five areas, recreating shallow areas of clean gravel with fast flows across them. The aim of the project was to enhance the spawning potential for Thames fish species, such as chub, barbel, gudgeon and dace.

Ms. Rhymes added: “The presence of brown trout, which we believe are around 15 months old, has been an unexpected but very welcome bonus of the project.  We’ll be keeping a close eye on their progress in the future.”