Securing Biodiversity in Breckland - European Commission

More ambitious possibilities that could be explored include the potential to provide unite and linkEriswell Low Warren SSSI through to Foxhole Heath SSSI. With goodwill and appropriate agrienvironmentagreements it may also be possible to link these to Codson Hill via existing arablereversion sites.At a larger scale, there is potential to provide corridors to connect more widely dispersed andseparated units. It is important that any corridor or dispersal network provides suitable habitat forreproduction and sustaining populations within the corridor, so that over longer time periods gradualpercolation may allow population spread among remnant sites. A simplistic approach that merelyaims to create some kind of grassland between sites is unlikely to reflect the complexity of ecologicalprocesses required for the mobility and interchange of priority species.To create connectivity networks among sites, instead of focusing on creating linear strips of grassheathhabitat, strategic planning should focus on: Buffering existing track-ways and track verges with cultivated margins and agri-environmentagreements in the arable landscape, to provide complexes of juxtaposed habitats in longbands (Figure 35). On creating broad ruderal and disturbed highways for invertebrate and plant dispersal (bypercolation) through the forest landscape.In the forest landscape, fire-routes and ride (track-way) verges already provide a widely dispersednetwork. Work by the Conservation Ecology Research Group at the University of East Anglia showsthis can support considerable diversity of specialist heathland carabids and spiders includingnationally notable and scarce species (Lin 2005; Bertoncelj 2010; Pedley unpublished data). Howeverthis network is spatially interrupted and incomplete due to shading of track elements when adjacenttree crops pass thicket stage. We therefore recommend focusing on creating wide permanently unshadedinvertebrate superhighways, flanked by disturbed strips of ground (e.g. with ploughing or turfstripping treatments to create bare disturbed sand and chalk). This could provide suitable conditionsfor resident populations that could slowly percolate providing connectivity: Within the forest landscape (linking existing open areas, providing enhanced dispersal intoclear-felled and restocked areas) Across the forest landscape (potentially linking key heathland SSSIs, for example linkingWeeting Heath to Cranwich and Grimes Graves (Figure 34); Lakenheath Warren to WangfordWarren; Lakenheath Warren to Thetford Golf Course and Marshes via High Lodge; and linkingWest Stow and Ramparts Field to Berners Heath).All corridors will inevitably be opportunistic, but should be planned in relation to soil types, withpreference to the extremes of the chalkiest, most sandy and acid soil types.Ultimately an ideal would be to overlay the connectivity networks with patterns of revitalised stockmovements to encourage dispersal of plants and seeds, but some dispersal of seeds and movementof invertebrates can nevertheless occur without this.Recommendations: Opportunities should be taken to strategically buffer and link existing SSSI units into largecontiguous networks wherever possible, allowing integrated grazing management andenhanced populations of specialist assemblages.195