Case Study 1 - Lestes dryas in the Weald
This map shows the distribution of this species in Eastern England. The blue squares show that the stronghold is the Thames Estuary and the Pingos of Norfolk. It has apparently been lost from most of its central and southern England localities and it is those losses that this study addresses. Are they really losses or just under recording. Let me explain what I mean.
In the late 1940s Norman Moore discovered a number of colonies of L. dryas in East Sussex around the River Rother. Norman and I wrote up these findings (Chelmick and Moore 2009). It was last recorded in 1952 and, apart from isolated records there have been no colonies recorded since. Our paper suggested that the reason for the demise was changing agricultural practice. I wonder whether it was true!
In 2009 at Sissinghurst Castle (National Trust) a new wetland was created at the bottom of a valley surrounded by cereal fields. In 2012 two species of Lestid: L. dryas and L. sponsa were found at this new site. The first reliable records for this area and just north of the original Norman Moore sightings.
This map shows the distribution of this species in Eastern England. The blue squares show that the stronghold is the Thames Estuary and the Pingos of Norfolk. It has apparently been lost from most of its central and southern England localities and it is those losses that this study addresses. Are they really losses or just under recording. Let me explain what I mean.
In the late 1940s Norman Moore discovered a number of colonies of L. dryas in East Sussex around the River Rother. Norman and I wrote up these findings (Chelmick and Moore 2009). It was last recorded in 1952 and, apart from isolated records there have been no colonies recorded since. Our paper suggested that the reason for the demise was changing agricultural practice. I wonder whether it was true!
In 2009 at Sissinghurst Castle (National Trust) a new wetland was created at the bottom of a valley surrounded by cereal fields. In 2012 two species of Lestid: L. dryas and L. sponsa were found at this new site. The first reliable records for this area and just north of the original Norman Moore sightings.
At the BDS Annual Meeting in 2013, Carl Sayer of UCL gave a paper on the restoration of marl pits in Norfolk and the subsequent reappearance of L. dryas. Such pits were created to provide marl used to improve soil quality. They can be found all over the country including Sussex and Kent. My colleague John Luck took up the batten approaching and badgering land owners and farmers and can you believe it he struck lucky with an amenable farmer dedicated to nature conservation. In July 2014 John and I visited the farm and set off across the fields. There were many old marlpits, just woodland now but we found one choked with rushes and sedges and virtually dry. Can you believe it there it was, a male L. dryas. Later that day we found another openish choked pit and this time with ovipositing pairs. John and I wrote this up (Chelmick and Luck 2016). The picture shows John Luck standing in the middle of the new Kent L. dryas site
These marl pits are found in many parts of the country, the problem that they are usually found deep in inaccessible farmland rarely visited by naturalists. Could it be that many of those old central England sites for L. dryas were marl pits or at any rate old farming ponds. Based on our Weald experience perhaps with a few more persisitent coves like John Luck there would be a different story.