North Wales Rivers Trust

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The Bullhead makes a comeback

With North Wales rivers grappling with declining water quality and freshwater species in freefall, the North Wales Rivers Trust reports the presence of the protected Bullhead fish in the Afon Bach and the critically endangered European Eel.

Bullhead- sensitive to poor water quality

The Afon Bach on the Clwyd is currently classified as 'bad' on the latest national Water Framework Directive ( WFD) due to a lack of fish diversity (noted fish included European eel, bullhead, and trout). 

North Wales Rivers Trust's Lead River Restoration Officer, Dr Liam Whitmore, said, 'This is an exciting development for the Bach. It shows that it is possible to see the return of sensitive keystone species with a collaborative and focused effort to restore rivers. Bullheads are highly sensitive to water quality changes and poor habitat, and they are a good indicator that species such as salmon and trout could return. 

Critically endangered European Eel

Over the last few months, Dr. Liam Whitmore, a specialist in Environmental DNA, has been carrying out eDNA tests on the Afon Bach and other rivers across North Wales to detect the presence of freshwater species, including mammals and invertebrates.

Other freshwater fish species evident in the Afon Bach eDNA analysis include Eurasian minnow, brown trout, three-spined stickleback, and stone loach.

Dr Liam Whitmore taking eDNA samples from North Wales rivers.

Dr Liam Whitmore added that all living things leave traces of their DNA in the environment (eDNA). Utilising this powerful water sampling technology, we can capture these DNA traces and determine species composition insights as part of our assessments of the health of our river systems and the impact of our work over time.'

The North Wales Rivers Trust has completed a series of targeted interventions on the Afon Bach over the last 18 months. Working with landowners to fence out thousands of cattle to stop them from defecating in the river system, trampling vital spawning grounds, and planting trees to keep the river temperature cool- as fish are sensitive to temperature changes. North Wales Rivers Trust installed a series of live willow bank revetments to reduce sediment loss and bank erosion and increase habitat for juvenile fish.

The North Wales Rivers Trust is part of the wider Clwyd forum focused on improving the water quality of the Clwyd through a series of Nature Based Solutions (NBS) with other key organisations. The key focus for all has been on water quality improvements and habitat restoration.

The North Wales Rivers Trust is now building on this success by targeting interventions to reduce heavy metals and salinity from road salt entering the watercourse and groundwaters from the A55 motorway.