26 July 2010
The Purbeck Mason Wasp is found only on the Isle of Purbeck in Dorset. The wasp stocks its burrow with caterpillars of a small moth which feeds mainly on Bell heather. The adult wasps bite holes in the flowers of this heather to obtain nectar, so the association with this plant is very close.
Latin name: Pseudepipona herrichii
Its populations have declined over much of its previously occupied area but changes in heathland management practices have provided new areas which are being colonised when nesting and foraging habitats become available. No accurate population figures exist although it is estimated that there are unlikely to be more than 250 nests present in any one year.
Where to see and when:
Adult wasps can be seen foraging for moth larvae amongst the flower heads of Bell heather during the summer. Nest burrows can be found in clay outcrops amongst the chalky margins of tracks and paths.
What’s being done:
Conservationists are undertaking detailed studies of the species to understand what the problems are and to improve heathland management programmes. Foraging adults and nest aggregations are monitored every few years.