The ladybird spider is found on dry sandy heaths with bare or lichen covered patches, where it forms burrows in the sandy substrate and is protected from the wind by the surrounding heather. It preys on insects blundering into the external web. Females will only leave their burrows if conditions deteriorate and they have to relocate. Males only leave the burrow to mate, for a period of about two weeks in early summer. Females are able to survive for several years as adults before breeding. This species needs very warm, dry conditions and may not breed in wet years. The species has a long life cycle of up to eight years and may therefore be slow to respond to improved habitat conditions. Until recently this species was considered conspecific with Eresus cinnaberinus (=niger) but northern and montane European populations, including the British population, have been referred to E. sandaliatus.
Until the late 1920s the species was recorded from several sites in Dorset but it was then thought to have become extinct in Britain. Although was rediscovered in 1979, it is known from only a single site, in Wareham Forest, where the exceedingly small population is less than 300 adults. This is slowly increasing but the population remains vulnerable. There are likely, but unconfirmed records from Kynance Cove in Cornwall, the Undercliffs of the Isle of Wight, and Kirkby Moor in Lincolnshire. It is rare and apparently declining in northern Europe (Denmark, Germany, Netherlands and Sweden) and otherwise occurs only in areas of the Alps and the Pyrenees.
In Great Britain this species is classified as Endangered. It is given full protection under Schedule 5 of the Wildlife and Countryside Act 1981.
Current factors causing loss or decline
Encroachment and shading by Rhododendron, pine and bracken.
Competition from southern wood ants may be a factor.
The ladybird spider has been the subject of an NE Species Recovery Programme since 1991, under which FE has carried out extensive habitat management and enlargement of the occupied site.
There has been regular monitoring of the known population and considerable survey for additional sites.
An experimental captive breeding programme has been established with specimens imported from Denmark. These specimens will not be used for establishment in the UK.
Action plan objectives and targets
Maintain the population size at its known site.
Enhance the population size at Wareham Forest by 2010.
Restore populations to two suitable sites within the historic range by 2010.
Maintain an ex-situ population to provide material for reintroductions and ecological research.
Proposed actions with lead agencies
Policy and legislation
Site safeguard and management
Prevent external activities threatening the existing population. (ACTION: NE, FE)
Remove encroaching pine, Rhododendron, bracken and scrub at appropriate intervals to maintain areas of bare ground and to encourage the regeneration of heather. (ACTION: NE, FE)
Where possible, increase the available habitat at the known site and adjacent areas, and attempt to link up existing fragments of habitat. (ACTION: NE, FE)
If new populations are found on any SSSIs, ensure that the species is included in relevant site management documents. (ACTION: NE)
Consider notifying any newly discovered sites for the species as SSSIs. (ACTION: NE).
Species management and protection
Establish the ladybird spider on at least two additional sites within the former range by 2010. (ACTION: NE)
Advise landowners and managers of sites where the ladybird spider is introduced about the habitat requirements and site management requirements of this species. (ACTION: NE).
Future Research and Monitoring
Undertake surveys to determine the status of the species. These should concentrate on heathland areas within a radius of 30 km of the extant site. (ACTION: NE)
Continue monitoring of extant population and initiate monitoring of any establishments. (ACTION: NE)
Consider genetic analysis of the population to identify inbreeding problems. If further colonies are discovered, take advice on the desirability of facilitating gene flow between populations, at least in the origination of new colonies. (ACTION: NE)
Communications and Publicity
Promote opportunities for the appreciation of the species, and the conservation issues associated with its habitat. Continue to use this species as a flagship to inform and popularise the problems faced by heathland invertebrates and spiders in general. (ACTION: NE)
Links with other action plans
Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume IV: Invertebrates (March 1999, Tranche 2, Vol IV, p433)