A French spider-eating wasp has been found in Britain for the first time. Episyron gallicum, as the wasp is known to entomologists, was found breeding in a quarry next to the RSPB’s headquarters in Sandy, Bedfordshire.
RSPB staff have worked with the quarry’s owners, Lafarge Aggregates Ltd, to create a tailor-made habitat that is ideal for rare insects. The wasp was discovered after Lafarge agreed to fund a survey of the quarry to see if the work had been successful in attracting insects to the site. Normally a Mediterranean species, the nearest it has been to Britain before now is central France.
Peter Bradley, site manager at the RSPB reserve, is convinced that the work carried out by the RSPB and Lafarge has made it possible for the creature to make its home on this side of the Channel.
‘It is a species of specialist wasp that lives in loose dry sand and I’m pretty sure it’s living here and breeding,’ he said.
‘What usually happens with quarries is they are great for these rare invertebrates for a short period of time, while there is lots of disturbed, dry sand and cliff faces. But after a few years they get filled in or nicely profiled by grass or the cliff face runs out of coarse material.
‘The idea here was to create a structure that naturally creates new areas of loose sand by gradually eroding. This is a way of managing quarry restoration that is exceptionally good for interesting wildlife. It’s obviously worked very well here.’
Gavin Broad, a zoologist with the Biological Records Centre, said climate change may have combined with work done at the quarry to create good conditions for the colonist.
He said: ‘A lot of insects are constantly getting blown about all over the place and will often end up in unsuitable places, but as soon as the weather is right they will stay on. The change to warmer summers and winters is going to help them. The quarry work means it is absolutely ideal for this kind of wasp. They love warm, sandy banks.’
Tim Deal from Lafarge added: ‘It’s great that we have found something of national interest, very possibly as a result of the restoration work we have done at the quarry. We are very pleased to see that what looks like quite a barren landscape actually has quite a lot going on. The report has shown up some really good evidence of biodiversity, not just in extent but quality too.’
In total, 135 species of insect were found at the quarry ranging from bees, wasps and flies to earwigs, ants, crickets and grasshoppers. Among the other stars of the survey were an endangered robberfly, which was previously confined to The Brecks area of Norfolk and Suffolk, a ground-nesting weevil-hunting wasp and several kinds of rare bees.