Current status
The field-cricket is a flightless insect of short, warm, tussocky grasslands which have between 10 and 50% bare ground. Oviposition and early nymphal stages are associated with patches of bare ground. Later development and overwintering occurs within grass tussocks, at the base of which the field-cricket constructs its burrows. As such, it is a species of early- to mid-successional grassland rather than established meadows. This successional component may be naturally extended on steep, south-facing banks. The species reproductive success is naturally sporadic, with occasional large population increases interspersed with periods of several years when the population naturally decreases. One factor driving this pattern is the weather conditions over each yearly reproductive cycle; another factor is the availability of suitable sunny, bare ground for oviposition.
The field-cricket is an extremely rare, declining and vulnerable insect which, in the UK, is restricted to one natural population, consisting of three sub-populations, within one square kilometre in West Sussex. Two reintroduced populations have been established, both of which are also in West Sussex. Other reintroductions within its confirmed natural range are planned. This species has always had a very restricted range in England, being bounded (approximately) to the east by the River Arun, to the west by the Solent, to the north by the North Downs and to the south by the Isle of Wight. The majority of records are from sandstone areas, although there are a few from the chalk. Records from outside this area either refer to accidental imports from the Continent or, more often, to misidentifications of the call of the house cricket, Acheta domesticus. The field cricket is widespread in southern and central Europe, north to the Netherlands and Germany, although it is in severe decline throughout much of its range. Towards the southern edge of its range it becomes a montane species, being replaced at lower latitudes by Gryllus bimaculatus.
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
Inappropriate site management reducing the availability of bare ground areas.
Unfavourably warm winters followed by wet spring weather. This is a possible scenario under global warming.
Invasion of acidic grasslands by bracken.
Current action
This species has been part of the NE's Species Recovery Programme since 1991. Under this programme, a species action plan was written in 1995 and has been revised annually since then.
The last fully native population is, in part, on an SSSI. Both reintroductions are on SSSIs.
Action plan objectives and targets
Maintain populations at all known sites.
Enhance the population size at all known sites by 2010.
Restore populations to further suitable sites within the historic range to achieve a total of ten viable populations by 2010.
Maintain an ex-situ programme to provide material for reintroductions and ecological research.
Proposed actions with lead agencies
Policy and legislation
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 all occupied and nearby potential grassland habitat is appropriately managed by 2008. This should be achieved through a rotational programme of ground disturbance, and subsequent appropriate grazing or mechanical management. (ACTION: NE, MAFF)
Ensure that the habitat requirements of the field-cricket are taken into account in relevant development policies, plans and proposals. (ACTION: NE, LAs)
Consider notifying sites supporting viable populations of field-crickets as SSSIs where this is necessary to secure their long-term protection and appropriate management. (ACTION: NE)
Species management and protection
Maintain and, if necessary, expand the existing captive rearing and release programme until the English populations are considered beyond threat. (ACTION: NE)
Re-introduce the field-cricket to a series of sites to achieve a total of 10 viable populations. (ACTION: NE)
Advisory
Advise landowners and managers of the presence of the species and the importance of beneficial management for its conservation. (ACTION: NE)
Future Research and Monitoring
Conduct further targeted autecological research to inform habitat management. (ACTION: NE)
Establish a regular monitoring programme. (ACTION: NE)
Pass information gathered during survey and monitoring of this species to a central database for incorporation in national and international databases. (ACTION: NE)
Encourage research on the ecology and conservation of this species on an international level and use the experience gained towards its conservation in the UK. (ACTION: NE, JNCC)
Communications and Publicity
Promote opportunities for the appreciation of the species and the conservation issues associated with its habitat. This should be achieved through articles within appropriate journals, as well as by publicity leaflets. (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, p449)
Related links
ARKive Visit the ARKive website to view images and further information relating to this species