Young eels have been transferred from the Severn Estuary in the UK to the Vistula and Curonian Lagoons in Russia and Poland due to the degradation of their habitat in the Severn Estuary caused by modern agriculture and pollution. This transfer is seen as a way to restore the eels' numbers and is supported by the UK Joint Committee on Nature Conservation. The lagoons provide a more natural environment and free migration routes to the Baltic and Sargasso Sea, crucial for eel breeding. This relocation is viewed as a necessary step due to the challenges of restoring eel habitat in the UK.