Rare moth discovered in North Wales
A rare species of moth has been found on the Llŷn peninsula for the very first time, a sign of the thriving habitat being maintained there.
The Bog Grass Moth (Crambus silvella) was found at Cors Geirch National Nature Reserve, Gwynedd while conservationists were showcasing the fen’s fascinating invertebrate species.
The fen, which is home to all sorts of diverse species, is one of many sites monitored by Natur am Byth’s Llŷn and Ynys Môn project, an initiative that aims to protect some of North Wales’ most at risk species.
As part of Natur am Byth, Wales’ flagship species conservation programme, project officers, conservationists and enthusiasts were gathered at Cors Geirch to survey the invertebrate species there.
Three moth traps were set up and throughout one night 446 moths made up of 91 different species were collected. 19 of these were Bog Grass Moths, the first time the species has ever been recorded in the area.
Several rare species at the site, including the Six Spotted Crane Fly (Idiocera sexguttata) and the Black Nightrunner Ground Beetle (Chlaenius tristis), rely on the fen’s alkaline rainwater to survive. This kind of habitat also allows wet sedges to grow which is the only food source for the Bog Grass Moth’s larvae.
Steve Palin and Charles Aron, local lepidopterists who identified the moth, said:
“The beauty of trapping moths is you just never know what’s going to turn up! But finding the Bog Grass Moth, an incredibly scarce moth, was a special surprise.
“It’s a significant addition to our knowledge of the region’s winged insects and demonstrates the value of targeted moth recording in these specialist fen habitats, where there is clearly still much to discover.”
Clare Sampson, Natur am Byth Project Manager for RSPB Cymru, said:
“Along with Natural Resources Wales staff, local contractors and volunteers, Natur am Byth has been opening up the delicate, wet, calcium-rich flushes that are home to these rare invertebrate species.
“While many fens suffered over the hot, dry summer, not only did we find healthy numbers of the Black Night-runner and Six-spotted Cranefly at Cors Geirch this year, but we also discovered this wonderful and rare species of moth.
“At least 80 per cent of UK peatlands have been lost or damaged, meaning rare species that depend on specific habitats like this struggle to survive. But with careful management, these important fen sites can be managed and maintained so that future generations can continue to make new discoveries”.
The monitoring carried out at Cors Geirch is one of many activities organised under Natur am Byth! that aims to connect people with nature. Those interested can get in touch with the programme through naturambyth@naturalresources.wales and find project information, species profiles and volunteering opportunities.