A reservoir in north Wales has been drained by the water company Hafren Dyfrdwy to carry out what it described as essential safety works, but the timing of the operation has raised serious ecological concerns.
According to local conservation groups, the drawdown occurred during the peak of the amphibian breeding season, when thousands of common toads had recently migrated to the site to spawn. As a result, more than 1,000 toads are feared to have died – it's a big hit to a native species already in long-term decline across the UK.
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As many as 1,000 toads killed
The Nant-y-Ffrith reservoir in Denbighshire had functioned as a critical breeding habitat within a wider network of wetlands, grassland and woodland. Amphibians such as toads, frogs and newts depend on stable water bodies for reproduction, and many species return to the same breeding location each year. Sudden drainage doesn't simply displace them, it can lead to direct population decline, disrupting an entire life cycle.
The ecological impacts extend beyond amphibians. The reservoir and its surrounding habitats supported a range of bird species, including lapwings, curlews and reed buntings, as well as aquatic invertebrates and otters. Removing the reservoir effectively eliminates numerous feeding and nesting grounds, triggering cascading effects throughout many ecosystems.
The reservoir's premature drawdown is criticised
Volunteers and wildlife groups have been particularly critical of the timing, noting that mitigation could have been achieved by delaying the works until after the breeding season – a matter of only a couple of weeks.
Hafren Dyfrdwy stated the draining took place in order to carry out essential safety improvements. Experts warn that recovery may be slow: amphibian populations are vulnerable to sudden losses, and recolonisation of breeding sites is uncertain when habitats are fundamentally altered as they have been at the Nant-y-Ffrith site.
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