Amateur
Entomologists'
Society

Guidelines to local BAP groups on the selection of priority habitats for invertebrates

Invertebrate Link - Joint Committee for the Conservation of British Invertebrates

Action plans for species and habitats of local concern play an important role in local BAPs. Unfortunately, the writing of invertebrate Species Action Plans can be quite a headache for local BAP groups because of the large number of species and the poor knowledge of their status and conservation needs in many areas. For these reasons, invertebrate issues of local concern are best tackled through habitat action plans. This leaflet describes nine habitats of particular invertebrate value that are not covered by existing national plans and that should be identified as priority habitats if this is appropriate for your area. A contact name for further advice is provided for each habitat. Specimen plans and lists of key species may be available from these contacts.

  1. Mature trees

    Mature trees are of great value for invertebrates associated with dead wood. Good examples can often be found along riversides and in hedgerows. Local mature tree habitat action plans can be viewed as the wider countryside companion to the national lowland wood-pasture and parkland habitat action plan. Indeed, action to conserve mature trees in the wider countryside is crucial to the viability of pasture-woodland sites which are isolated and vulnerable to extinction events.

    Main invertebrate groups:
    mostly beetles, spiders and two-winged flies, but also moths, wasps and other small groups.

    Other important groups:
    hole-nesting birds, bats (roosting sites), fungi, lichens and mosses.

    Key issues:
    Mature trees are often seen as safety hazards, but sympathetic management, e.g. pollarding, can both avoid felling and meet safety requirements. Widescale training and promotion of sympathetic management is a crucial element in any mature tree habitat action plan. Intensive farming practices, e.g. root ploughing and inorganic fertilization, are damaging trees in fields and hedgerows.

    Mature trees are features of both the urban landscape and rural villages and provide great opportunities for community involvement in survey and influencing management.

    Contact: Keith Alexander, Ancient Tree Forum, c/o National Trust, 33 Sheep St., CIRENCESTER, Gloucs, GL7 1QW. Tel: 01285 657935, Fax: 01285 657935, Email: XEAKXA@smtp.ntrust.org.uk
  2. Springs and associated flushes

    Springs are relatively permanent features of the landscape. Associated flushes often have a long hydrological continuity which allows an interesting flora and fauna to build up over time, especially when they form a spring-line where an aquifer surfaces. Unfortunately, their value for biodiversity is poorly recognized by many conservation bodies.

    Main invertebrate groups:
    soldier flies, crane-flies, water beetles and other groups.

    Other important groups:
    flowering plants and mosses.

    Key issues:
    Because they are small-scale features, springs and flushes are vulnerable to local land use change and disturbance by modern machinery, particularly in agricultural landscapes. They have even been damaged by pond creation schemes as part of ill-advised conservation schemes. The best remaining sites need to be located and landowners encouraged to maintain continuity of management.

    In some areas, springs have dried out because of water abstraction from the aquifer and their sensitive invertebrate fauna has been either destroyed or severely reduced.

    Contact: John Kramer, Dipterists' Forum, 31 Ash Tree Rd, Oadby, LEICESTER, LE2 5TE. Tel: 0116 271 6499, Fax: 0116 267 7112.
  3. Exposed river sediments

    River banks of shingle, sand and silt which are submerged over much of the winter, but exposed during low flows in the spring and summer are breeding grounds for a huge number of specialized invertebrate species. Large rivers support the greatest diversity of species, although individual smaller streams can often be of exceptional quality. Exposed river sediments could be combined with floodplain wetlands to form a large rivers habitat action plan (see 4 below) or incorporated into a fast-flowing streams habitat action plan (see 6 below).

    Main invertebrate groups:
    beetles, flies and spiders.

    Other important groups:
    yellow wagtail, common sandpiper and other birds.

    Key issues:
    River sediments are extremely vulnerable to changes in river management and catchment land use, even when this occurs at some distance upstream. Retention and maintenance of exposed sediments needs to be incorporated into LEAPs, river restoration designs and general river management objectives.

    Changes in adjacent land use can affect the hibernation sites needed by most species. It is necessary to control access of grazing stock to important sites.

    Contact: Derek Lott, Leicestershire Museums, Arts & Records Service, County Hall, Glenfield, LEICESTER, LE3 8TB. Tel: 0116 265 6790, Fax: 0116 265 6788, Email: dlott@leics.gov.uk
  4. Floodplain wetlands

    Floodplains of larger rivers often contain swamps, marsh and wet woodland in undisturbed abandoned river channels and ditches which can be of great value for invertebrates, even though they are often too small or shaded to be of much interest for birds. Shallow pools in gravel pits and their marginal areas can attract some elements of this fauna.

    Main invertebrate groups:
    beetles, flies and snails.

    Other important groups:
    birds (mainly gravel pits and open sites).

    Key issues:
    Regular winter flooding is an important feature of these sites. Important sites should not be included in areas of benefit from flood alleviation schemes.

    Invertebrates of well-established floodplain wetlands are often very sensitive to disturbance, so important sites should be protected from overgrazing, infilling and conversion to fishing lakes. Areas of minimum intervention should be incorporated into the design of wetland creation schemes.

    Contact: Derek Lott, Leicestershire Museums, Arts & Records Service, County Hall, Glenfield, LEICESTER, LE3 8TB. Tel: 0116 265 6790, Fax: 0116 265 6788, Email: dlott@leics.gov.uk
  5. Small ponds

    Field ponds, woodland ponds and Sphagnum pools are all good examples of small-scale features which can provide distinctive invertebrate habitat. Even seasonal pools can be valuable for invertebrates. They are scattered throughout both lowland and upland landscapes and provide good opportunities for community involvement.

    Main invertebrate groups:
    dragonflies, beetles, caddis flies, water bugs, flies, leeches, flatworms, spiders and snails.

    Other important groups:
    amphibians, mosses, charophytes, grasses, sedges and other flowering plants.

    Key issues:
    Infilling and lowering of water tables have led to a decline in pond numbers and increased problems of pond isolation. Pollution damage caused by eutrophication, acidification, pesticides and urban runoff is believed to be widespread. Poor management practices are also an issue, particularly overdeepening of seasonal ponds. In all cases, there is a need to create high quality new ponds in order to replace the open water stage of mature ponds as they succeed to seasonal and terrestrial habitats. Recent advances in pond ecology recognize a wide range of pond types requiring different management approaches. Training and the promotion of good practice among conservationists is as important as engaging landowners in maintaining the density and variety of ponds in the landscape.

    Contact: Penny Williams, Pond Action, Oxford Brookes University, Gipsy Lane, Headington, OXFORD, OX3 0BP. Tel: 01865 483249, Fax: 01865 483282, Email: jbiggs@brookes.ac.uk
  6. Fast-flowing streams

    Rich invertebrate communities can be found in and alongside streams containing natural riffle and pool systems and a gravel substrate. Ravined sections running over exposed bedrock and associated moss carpets also support characteristic invertebrate communities.

    Main invertebrate groups:
    mayflies, stoneflies, caddis-flies, beetles and flies.

    Other important groups:
    mosses, fish and birds.

    Key issues:
    In agricultural and built-up areas, the channels of many streams have suffered being straightened or otherwise modified to the detriment of their flora and fauna. Opportunities now exist for restoring them to their former natural, meandering courses with associated features of value for biodiversity.

    Contact: Patrick Armitage, IFE River Laboratory, East Stoke, Wareham, BH20 6BB. Tel: 01929 462314, Fax: 01929 462180, Email: p.armitage@ife.ac.uk
  7. Post-industrial and urban demolition sites

    Derelict sites containing bare ground incorporated into a mosaic of different types of vegetation can be of great interest for pioneer species of invertebrates. Sites on nutrient-poor, compacted or contaminated soils maintain areas of sparse vegetation for longer and so build up a richer fauna. These sites provide great opportunities for linking biodiversity objectives to educational and leisure initiatives. Vegetation mosaics containing bare ground are also important in heathland and calcareous grassland and should be considered in appropriate habitat action plans.

    Main invertebrate groups:
    bees and wasps, beetles, bugs, flies, grasshoppers and spiders.

    Other important groups:
    flowering plants, reptiles and birds.

    Key issues:
    Mineral extraction provides great opportunities in the restoration phase for creating bare ground habitats of value, not only for invertebrates, but also for other groups. With careful planning, post-industrial and urban demolition sites can support valuable invertebrate communities pending redevelopment. Their proximity to centres of population offers educational opportunities as well.

    Contact: Brian Eversham, The Wildlife Trust for Beds., Cambs, Northants. and Peterborough, Lings House, Billing Lings, NORTHAMPTON, NN3 8BE. Tel: 01604 405285, Fax: 01604 784835, Email: beversham@cix.co.uk
  8. Soft-rock cliffs

    Limestone, sandstone and clay cliffs can attract an outstanding invertebrate fauna where the pace of erosion allows the development of a mosaic of bare ground and pioneer vegetation. Seepages on landslip areas are a critical feature for most species. Good sites are known from South Devon, Dorset, the Isle of Wight, Norfolk and Yorkshire, but there are many localities waiting to be discovered and sites of local value could crop up in most coastal regions.

    Main invertebrate groups:
    mainly bees and wasps, beetles and flies, but also spiders and snails.

    Other important groups:
    flowering plants and lichens.

    Key issues:
    Cliff stabilization can lead to both short-term and long-term loss of important habitats and should be avoided on important sites.

    Important sites should be protected from nearby abstraction of ground-water which can dry up seepages and springs.

    Contact: Martin Drake / Roger Key, English Nature, Northminster House, PETERBOROUGH, PE1 1UA. Tel: 01733 455000, Email: martin.drake@english-nature.org.uk
  9. Freshwater seepages on saltmarshes

    Saltmarsh is well recognized as a valuable habitat. Attention is drawn here to the special invertebrate fauna of freshwater seepages onto saltmarsh. This habitat is highly localized and, like much of the higher tidal zone, particularly vulnerable to adjacent land uses.

    Main invertebrate groups:
    flies.

    Other important groups:
    none known.

    Key issues:
    Sites need protection from drainage and water abstraction on nearby land which can remove the source of water and from pollution associated with agriculture or seaside development which can have a big impact on such small flows of water.

    Sensitive areas can be damaged by excessive trampling. Sea walls and other developments should be positioned well above the higher tidal zone and should not interfere with the hydrology of the seepages.

    Contact: Alan Stubbs, 181 Broadway, PETERBOROUGH, PE1 4DS. Tel: 01733 346648.

Further reading

Fry, R. & Lonsdale, D (eds.) (1991). Habitat Conservation for Insects - a neglected green issue. Amateur Entomologists' Society, Middlesex.

Jeeves, M.B., Kindleysides, D., Bullock, J.A. & Lott, D.A. (eds.) (1998). Biodiversity Challenge for Leicester, Leicestershire and Rutland. Leicestershire & Rutland Wildlife Trust, Leicester.

Kirby, P. (1992). Habitat Management for Invertebrates: a practical handbook. Royal Society for the Protection of Birds, Sandy.

Read, H.J. (ed.) (1996). Pollard and Veteran Tree Management II. Corporation of London, Burnham Beeches.

Authors

Derek Lott & Alan Stubbs, 27/04/1999