Twyford Down Project
Progress to Date
The three areas of downland restoration, though in different stages of colonisation,
are progressing well. On Arethusa A, the first area to be completed, the turf translocations
have been very successful so far. In the machine-
The sown grassland on Arethusa B is maturing more slowly than A with fewer coarse
grasses. Although the colonisation is slower it is forming an open-
The invertebrate populations are also developing as expected. The initial large numbers
of early invasive species are decreasing, to be replaced by the true downland species.
At the Public Inquiry, fears were expressed about the future of the Chalkhill Blue butterfly on the Dongas following the construction of the road. In fact there is no evidence that the population of this species on the Dongas is declining; actually in 1995 it increased, following the national trend. To this can be added a flourishing new population on the Arethusa A area and both the Arethusa B and A33 restoration sites are being colonised. All the colonial species of butterfly that inhabited St Catherine's Hill and the Dongas SSSIs now have discrete additional populations established on the Arethusa Clump restoration area, many at a higher density than on the rest of the reserve.