The construction of special passes that allow elvers to move past river barriers that would otherwise obstruct their upstream migration has been identified as one of the measures necessary to contribute to the recovery of the Critically Endangered European eel.
We have made a number of improvements to the River Lee Navigation to encourage the passage of elver and enhance their watery homes, as part of a series of works on the waterways ahead of the Olympics. Working in partnership with the Environment Agency, we've built passes at Lea Bridge Weir, Bow Locks and on the Three Mills channel. Funding was secured by the Environment Agency to build the passes and we will manage them into the future. We have also separately installed elver passes at Three Mills Lock which will help with future monitoring.
This work has given elvers a helping hand to pass the barriers separating the river from the tidal Thames, leaving them free to migrate upstream. The elvers that make this journey will live for many years in the River Lee, slowly maturing before returning to the Sargasso Sea to spawn.
Improving water quality
Researchers from the Zoological Society of London (ZSL) have confirmed that elvers are using the newly installed pass at Bow Locks to access the River Lee. Thirteen elvers were recorded this year. With funding from the Esmee Fairbairn Foundation, ZSL has been working with volunteers from Thames 21 to monitor the pass at Bow Locks for the migrating elvers. This monitoring programme will be extended in 2013 to include the other elver passes in the Lee catchment.
The Lee was historically an industrial river and suffered from heavy pollution. We are committed to continual improvements to the Lee and have already put significant investment in to recent works including installing two kilometres of reed beds, dredging the river and managing invasive plants to improve water quality and habitat for all wildlife.
Leela O'Dea, environment manager at the Canal & River Trust, says: “Confirmation that elvers are migrating into the River Lee is extremely exciting. The Canal & River Trust has really invested in transforming the Lee from a heavily polluted waterway into the important wildlife habitat it is today, and having elver in the river really is the icing on the cake. What an incredible journey they've undertaken, travelling all the way from Bermuda to their spiritual home in the East End!”ZSL's Joe Pecorelli, says: “It has been fantastic to work with the Canal & River Trust and Thames 21 this year on this important project and we look forward to working with them to improve the River Lee for eels in the future.”
