The discovery at Woodwalton Fen National Nature Reserve (NNR) is significant as it demonstrates the resilience of the species when given the right conditions. The site is all that remains of a great wetland around Whittlesey Mere which was drained in 1851, leading to the loss of many species of wildlife. While the tansy beetle initially survived, its isolation was thought to have led to its ultimate extinction in Woodwalton in 1973, the date of its last recorded sighting, so it was a great surprise to entomologist, Dr. Peter Kirby, to discover a small population when carrying out ditch surveys for Natural England at Woodwalton this summer.
Dr Kirby said: “It is not uncommon for invertebrate populations to survive at extremely low levels for many years until conditions become suitable for an expansion and that appears to be what has happened here.”
Alan Bowley, Senior Reserve Manager at Natural England said: “This is such an exciting find. Woodwalton Fen is an isolated fragment of a once much larger wetland and so rare animals are always at risk of extinction, but this demonstrates how important these sites are for providing a refuge for these species to survive against the odds. There is only one other site in Britain where this beautiful creature is found and we will be working hard to try and ensure that it can flourish here.”
Natural England has been working closely with partners on the Great Fen vision to create new habitat around the NNR, and with the Tansy Beetle Action Group (TBAG) to study how best to improve conditions for the beetle. So the fact that it still living in the Fen is a real boost to those efforts.
The rare and visually stunning iridescent green tansy beetle (Chrysolina graminis) – was believed to have one remaining stronghold in the UK on a 30km stretch of the banks of the river Ouse in York. Now a momentous discovery has shown the existence of another population in the East Anglian fens.
Vicky Kindemba from Buglife and co-chair of TBAG said: “This is fantastic news for our amazing tansy beetle! This rare beetle now has a real chance at survival by expanding into the Fens. However, we still need to work hard to help it, and we would like everyone to get involved by ‘Adopting a Tansy Beetle’ at www.buglife.org.uk/adopt-tansy-beetle”