The River Thame, has always had small populations of barbel, especially in the middle and lower reaches of the main river. Historically, these populations may have been more substantial, especially before the Second World War. Whole scale land drainage, changing land use practices, river realignment and dredging post war has led to a deterioration in habitat quality and subsequently a decline in a number of fish populations, with gravel spawning species such as barbel, chub and dace particularly affected. Dredging of the main river and a number of its tributaries occurred regularly up until the 1980s.
The loss of habitat and more recent issues such as poor water quality from sewage treatment works, diffuse agricultural pollution and non-native invasive species (Signal Crayfish) have all had an impact, impinging on certain fish populations to varying degrees. It is widely recognised that barbel are one of the species that have been impacted on the most.
The Lower Thame Barbel Project was collaborative partnership project between Cuddesdon Mill Village Anglers Association (CMVAA), The River Thame Conservation Trust (RTCT), Thame Valley Fisheries Preservation Consultative (TVFPC), Greenford’s Ltd, The Barbel Society and the Environment Agency (EA) to improve habitat for Barbel in the Lower Thame.
As Part of this project 4 backwaters were created, 2 of which also functioned as cattle drinks and sections of river narrowed and gravel introduced to produce perfect breeding grounds for barbel. This project was completed in June 2018.
Why is this work necessary?
In the past we have routinely dredged, straightened and widened rivers for drainage purposes. Due to this rivers such as the Thame are over wide, deep and often lacking those features that would naturally occur in river systems such as braided channels and backwater. Features like these make a river system more resilient and provide a diversity of habitats which in turn means the river can support a larger variety of biodiversity.
In projects such as this we are recreating these features that have been lost due to human interference and restoring previous hydrological functioning of the river.