Introduction
From 2002 to 2004 John Dover ran an Earthwatch Discovery project in East Prawle, Devon, looking at butterflies and the Great Green Bush Cricket.
Background and context
Great Green Bush Cricket © Robert Thorne, Devon Wildlife
Trust
The Great Green Bush Cricket is an endangered insect; very little is known about its ecology. The Devon Wildlife Trust were keen to know more about it and the Earthwatch Discovery project, using volunteers as manpower, was a useful way of increasing knowledge while also studying other insects in the landscape. Volunteers stayed in East Prawle Village Hall, next to the Pig's Nose Inn, for their week-long stay in Devon.
Summary of project research
In 2002 John Dover and Paul Lunt, together with teams of volunteers, studied the great green bush cricket (Tettigonia viridissima) and the gatekeeper butterfly (Pyronia tithonus) in the field margins, green lanes and minor roads around the small coastal village of East Prawle in South Devon. Work involved the characterisation of the study site (plant species data, abiotic parameters, digital mapping using DGPS), distribution mapping of bush crickets, mark-release-recapture of gatekeepers, and butterfly transects for other butterfly species at the site.
In 2003 the project was overseen by Dave Skingsley, Kevin Reiling, Phil Smith and John Hayward of the Devon Wildlife Trust. It also included studies on craneflies and leaf-miners.
In 2004 the project was carried out in two stages. The first, with volunteers supervised by Paul Mitchell and PhD student Phil Smith, studied the movements of butterflies in the Devon landscape. This exciting manipulative experiment turned a single hedgerow into a green lane by adding a long parallel windbreak – the idea was to see if simply changing the local microclimate resulted in a better habitat for butterflies. The second, headed by John Dover and Phil Smith, involved tracking the movement of bush crickets using mark-release-recapture and radio tracking. Crickets were marked on their backs with a unique dot code, but also had reflective tags fixed to their hind legs to help relocate them. Some individuals had radio transmitters strapped to their backs.
Project impact
The investigations are concerned with how the landscape affects the movement of species and the spatial arrangement of important habitat resources. The work will be of value to the Devon Wildlife Trust in helping with conservation management advice.
For details about Earthwatch projects, please see: http://www.earthwatch.org/
Publications and reports
The project produced associated publications on other fauna of the area:
Smith, P.J. and Skingsley, D. R. (2007) Oil beetles (Col.: Meloidae) of the soft cliffs of Prawle Point, South Devon. The Bulletin of the Amateur Entomologists’ Society, 66(474): 188-194.
Skingsley, D R (2004) Snail density measurements from hedgerows at East Prawle (Devon). Mollusc World, March 2004, p. 6.