A BIOLOGICAL survey of land in Rassau identified for the £315 million Circuit of Wales racetrack has revealed a huge diversity of wildlife, according to Gwent Wildlife Trust.

The so-called "bioblitz" on the area, carried out in late June by GWT staff, volunteers and specialist recorders from across Gwent, recorded more than 300 species including plants, butterflies, dragonflies and birds.

Gemma Bodé, GWT’s conservation manager, said: “We knew this area was very good for wildlife but the incredible range of species and rarities found has surprised us and the local recorders.”

The area of land proposed for the Circuit of Wales is a mixture of heathland, wet flushes, streams and acid grassland. Some of the rarer plants found included bog asphodel, bog pimpernel and marsh violet. Birds recorded included wheatears, skylarks, ring ousel and red grouse.

GWT said the area seemed "incredibly valuable" for dragonflies with 12 species recorded including the keeled skimmer , black darter and the UK’s largest, the golden-ringed dragonfly, making it a "key site" for dragonflies in Wales.

The environmental trust said it continues to campaign against the proposals for the Circuit of Wales, which celebrated the beginning of a ten-year association with the British MotoGP earlier this month.

GWT said the results of the bioblitz "confirmed our fears for the rich wildlife that would be permanently destroyed if the proposals were to go ahead. Detailed plans for how this loss of wildlife would be adequately mitigated for are still not evident."

Work on the racetrack, which hopes to bring up to 6,000 jobs, is scheduled to begin at the end of the year.