Current status
This hoverfly is associated with valley mire on heathland and moorland, and possibly with other wetland, where its aquatic rat-tailed larvae are assumed to live in saturated peat in flushes, pools or stream edges The adults have been seen at flowers, including bramble, in drier areas, suggesting that a habitat mosaic within and beyond the valley mire is important.
Historically, Eristalis cryptarum was found in all counties of south-west England eastwards to the New Forest. However, it has suffered a major contraction in range, having lost strong populations in the New Forest and east Dorset in the post-war period. The last remaining British location is a small cluster of sites on Dartmoor. The species has a wide range in northern and temperate Europe and is recorded from central Siberia. In Denmark it has declined to endangered status, possibly close to extinction.
In Great Britain this species is classified as Vulnerable.
Current action
The Dartmoor population is within the SSSI.
Action plan objectives and targets
Maintain populations at all known sites.
Enhance the population size at all known sites by 2010.
Ensure that there are viable populations at five new sites within the historic range by 2010.
Proposed actions with lead agencies
Policy and legislation
Address the requirements of this species in the LEAP process and in relevant WLMPs. (ACTION: EA, IDBs, LAs, MAFF)
Where appropriate, include the requirements of the species when preparing or revising prescriptions for agri-environment schemes. (ACTION: NE, MAFF)
Site safeguard and management
Where possible, ensure that occupied sites are appropriately managed by 2005. (ACTION: Dartmoor National Park, NE, FC, MAFF)
Ensure that the species is included in site management documents for all relevant SSSIs. (ACTION: NE)
Consider notifying as SSSIs sites holding key populations of the species, where this is necessary to secure long-term protection and appropriate management. (ACTION: NE)
Species management and protection
Consider reintroducing to a series of sites within the former range if necessary to ensure that there are five viable populations. (ACTION: NE)
Advisory
Advise landowners and managers of the presence of this species and the importance of beneficial management for its conservation. (ACTION: NE, Dartmoor National Park, MAFF)
As far as possible, ensure that all relevant agri-environment project officers, and members of regional agri-environment consultation groups, are advised of locations of this species, its importance, and the management needed for its conservation. (ACTION: NE, MAFF)
Future Research and Monitoring
Undertake surveys to determine the status of this species. (ACTION: Dartmoor National Park, NE)
Conduct targeted autecological research to elucidate the causes of decline and inform habitat management. (ACTION: NE)
Establish a regular monitoring programme for this species. (ACTION: Dartmoor National Park, NE)
Pass information gathered during survey and monitoring of this species to a central database so that it can be incorporated in national databases. (ACTION: NE)
Communications and Publicity
Promote opportunities for the appreciation of this species and the conservation issues associated with this habitat. This should be achieved through articles within appropriate journals, as well as by a publicity leaflet. (ACTION: NE)
Links with other action plans
None given.
Publication details
Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume IV: Invertebrates (March 1999, Tranche 2, Vol IV, p169)
Related links
ARKive Visit the ARKive website to view images and further information relating to this species