The invasive fish threat to lakes and ponds and what needs to be done to eradicate it

The invasive fish threat to lakes and ponds and what needs to be done to eradicate it

By Richard Youle

Source: msn

11/25/2023

An invasive fish needs to be eradicated from five lakes and ponds in or near Llanelli and a toxic substance is one of the methods being considered, Wales's environment regulator said. Natural Resources Wales (NRW) said Sandy Water Park is one the five sites with the fish - topmouth gudgeon - but it declined to name the others. NRW said the use of a compound called rotenone was being considered, along with other treatment options.

Paul Hopkin, a naturalist who lives close to Sandy Water Park, has urged NRW not to use rotenone because of the knock-on impact he claimed it would have on fish-feeding birds and invertebrates. "The birds will leave if there's nothing for them to eat," he said.

Topmouth gudgeon are small freshwater fish from Asia which have spread into Europe. NRW said they reproduced rapidly, ate the eggs and larvae of other fish, survived in low-oxygen water conditions, carried the threat of new diseases or parasites - and were considered a high-risk invasive species.