Friday 18th September, 2020
This year’s electrofishing surveys have recorded another increase in the Elan’s juvenile salmon numbers. These exciting results build on improvements over the past four years to the river’s previously degraded ecology downstream of the Elan dam complex.
In 2016 the Foundation, with support from project partners Natural Resources Wales and Dwr Cymru Welsh Water, started an initiative to replace lost river gravels in 7km section of the river. Since then, we have re-introduced thousands of tonnes of new gravel, sourced from various sustainable sites across the Elan and upper Wye catchment.
While less sites were surveyed this year than the previous two years, salmon fry were found at every location for the first time, including as far upstream as our gravel introduction site just below the lowest dam (Caban Coch). For the first time since at least the 1970s (when surveys began), the whole length of the Elan from its confluence with the Wye up to Caban Coch is now being used by salmon to spawn in. The river, which represents 7% of the salmon spawning area of the Wye, is now one of the most important for salmon reproduction in the whole Wye catchment.
In 2016 the average number of salmon fry at each Elan survey site was 1.1. In 2019 this had increased to 11.8 and in 2020, the average was 20.7.
In addition to salmon fry, trout numbers (fry and adults) have more than doubled since the project started. This year, an eel was found at the introduction site for the first time too.
Yet despite this and exponential increases in average salmon fry densities in the Elan over the past four years, the future of the Elan gravel project is by no means assured. Finding source sites is proving more and more of a challenge with owners unwilling to allow us to take gravel, even when previous donor sites have been proven to recover quickly (usually within one or two years).
This year a generous owner has allowed us to remove around 300 tonnes of gravel from the upper Wye, which we will introduce to the Elan next week. However, we estimate that to continue or even maintain the improvements in river’s ecology, much more than this is required.
But for now, to anyone with an interest in river ecology, fish and the wider environment, the results of this project are something to behold.
The results of the Elan gravel of this project has enabled us to bid for and win funding to start similar projects in the Usk catchment, specifically in the Caerfanell stream that flows out of Talybont reservoir and the Afon Crai, an upper Usk tributary that is similarly impacted.
The consenting process is underway for both streams and we are currently undertaking baseline surveys with the gravel reintroductions to commence in 2021.