Summary details for Pelecopsis elongata (Wider, 1834)

Distribution

The species has been recorded in Britain only from Rothiemurchus Forest and Loch Garten/Abernethy Forest/Glenmore, East Inverness-shire, and near the south shore of Loch Rannoch, near Kinloch Rannoch, Mid Perthshire. It is widespread in central and northern Europe.

Habitat and ecology

P. elongata is confined to Caledonian pine forest. It occurs mainly in dry pine litter on rocks, but also on the lower branches of juniper and in moss. Adult males have been found in November, December, March and April, and females also during the summer. The main activity period is probably during the winter.

Status

The spider appears well-established in the Rothiemurchus/Abernethy areas, with recent records from both areas, but the populations may be threatened by unexpected habitat changes and climate change.

Threats

Areas of Caledonian pine forest are threatened with conversion to intensive forestry using Sitka spruce Picea sitchensis, lodgepole pine Pinus contorta and other alien species. The ecological requirements of P. elongata are not known in detail, but it is unlikely that conversion of open Caledonian pine forest to dense plantation forestry will maintain the habitat in a suitable state for this species. North of the Loch Garten RSPB reserve there has been a great deal of planting of Scots pine and lodgepole pine on land which previously supported scattered mature native pines. In Rothiemurchus Forest, 305 ha out of the 1539 ha of native pine were ploughed and planted in 1971 with Scots pine and lodgepole pine. Although 30 ha of Abernethy Forest were felled in 1984 before it was renotified as an SSSI, and a total of 226 ha were lost since 1977, it is now owned and managed by the RSPB.

Management and conservation

Regeneration of native pine should be encouraged by protection of the felled areas from grazing. At Rothiemurchus increased numbers of human visitors are thought to disturb the grazing deer sufficiently to reduce grazing pressure to the level at which pine regeneration can take place. In deer exclosures, natural regeneration can become as dense as a pine plantation and it may be necessary to thin pines in order to maintain an open forest with a varied age structure and good ground flora. The primary aim of the RSPB at Abernethy is to develop a self-sustaining native pine forest over the whole potential woodland area (Taylor in Aldhous 1995). Text based on Dawson, I.K., Harvey, P.R., Merrett, P. & Russell-Smith, A.R. (in prep.).