Cardiff University study on crayfish plague impact

Efforts to save the native white-clawed crayfish from extinction in Wales are showing "encouraging" results.

Natural Resources Wales (NRW) said an innovative project has seen approximately 4,000 of the threatened crustaceans reared and released here since 2009.

Meanwhile, Cardiff University research is looking at the impact of the larger North American crayfish on the native species.

PhD student Rhidian Thomas is set to present his research on the invasive signal crayfish at an international conference in Spain this month.

"It is quite a grave situation - the non-native species are continuing to spread and bringing crayfish plague with them," he told BBC Wales environment correspondent Steffan Messenger.