Open Mosaic Habitats on Previously Developed Land

Open mosaic habitats on previously developed land (‘brownfield’ habitat) include land that is or was once occupied by industrial or other human uses but which has now become disused, derelict or is currently unoccupied (in some cases they may still be in use). Such sites might include former colliery sites, disused quarries, spoil tips, restored opencast sites, pulverised fuel-ash (pfa) and metaliferous slag substrates, demolished or derelict factory sites, industrial lagoons, derelict railway land, redundant dockland, contaminated land, former refuse tips, etc. Where active mineral workings (including, for instance, quarries and opencast sites) and currently unused future investment plateaux have developed widlife interest, they should also be included within this definition. This land may occur in both built-up and rural settings.

Brownfield sites can often remain unused for many years and recolonisation by plants and animals on these undisturbed areas can lead to the development of a diverse flora and fauna with a complex succession of habitats forming a mosaic (patchwork), from bare ground to grassland, scrub and woodland. These areas often provide alternative habitats for many species that have declined due to loss of their native habitats in the wider countryside because of intensification of agriculture and urbanisation. Often the biodiversity value of these areas is underestimated and can be important for many species, especially plants, birds, mammals, amphibians and reptiles (herpetiles) and invertebrates.

Remnants of original habitats may remain within post-industrial sites which, although isolated and fragmented, can be important for biodiversity and act as a vital local genetic resource for recolonisation of disturbed areas. They can act as wildlife corridors in otherwise built-up or urban areas as well as providing valuable habitat in otherwise poor rural situations. Species may be introduced in dumped soil and ballast and exotic species may grow that are more often associated with other habitats or countries; these species may reflect the area's past international trade and could be seen to have some cultural value, e.g. certain annual species at Burry Port and Pembrey.

These areas are often valued by local people for casual recreation, such as for dog walking and often have informal amenity value.

In recent years, brownfield sites have become increasingly recognized nationally as important havens for wildlife. They often support protected species and may now carry designations in order to safeguard such species. However, increasing numbers are being designated on their own merit as habitats of importance develop. These include, for example, sites of former alkali tips, pulverised fuel-ash (pfa) lagoons, coal-spoil tips and gravel pits.

Current Status in Carmarthenshire

Many brownfield sites in Carmarthenshire are more important for biodiversity (whether plant, bird or insect) than large swathes of the intensively farmed countryside. Plants such as birds-foot trefoil and a variety of orchids, grayling and common blue butterflies, hovering kestrels and linnets on the gorse make these areas species rich – more so than some of the ‘wasteground’ sites subsequently restored to bland urban grassland. Many brownfield sites are situated near towns and villages with good opportunities for people to enjoy nature. One former settling lagoon at Pwll of the former Burry Port Power Station is actually a Site of Special Scientific Interest by virtue of an extraordinary mix of fenland and woodland plants, whilst another site nearby (‘Ashpits Pond’) is important for its wildfowl.

The majority of post industrial sites in Carmarthenshire occur in the south-east of the county, particularly on the Coalfield and the limestone quarrying areas, although most towns have derelict or development sites which are within the scope of this habitat definition.

Carmarthenshire’s brownfield sites include the following (this list is not exclusive):

Naturally re-vegetated colliery spoil

Many of the older tips have developed rich lichen and bryophyte communities, acid and neutral grassland, dwarf-shrub heath, wet flushes, scrub and woodland. Large examples of such sites remain, Llwynhendy, Bynea, Pentremawr, Pontyberem, Glynhebog, Cross Hands, Emlyn Penygroes, Tir-y-dail, Ammanford, Glanamman, Garnant and Amman Colliery, and many smaller sites are also still present within the coalfield.

Landscaped colliery spoil, restored opencast sites and development plateaux
These sites are often poor in wildlife diversity but may support significant breeding populations of species such as brown hare, skylark, curlew, little ringed-plover and lapwing. Many sites are being lost to redevelopment and it is important that adequate mitigation for the loss of valuable biodiversity habitat is included when development goes ahead.

Quarries

Both disused and active quarries can be important for wildlife. Carmarthenshire has a number of quarries designated as SSSIs. Currently unused areas in working quarries may also develop biodiversity interest in a relatively short time, particularly where there are seepages or areas of open water. In disused quarry sites, rock faces may provide nest-sites for birds of prey. Quarries may also develop woodland, scrub and grassland habitats supporting reptiles, amphibians and butterflies in addition to characteristic woodland herbs and grassland species. Rare species associated with semi-natural woodlands within unworked areas of limestone quarries include mezereon (Daphne mezereum), toothwort (Lathraea squamaria), yellow bird’s-nest (Monotropa hypopytis), herb Paris (Paris quadrifolia) and lily of the valley (Convallaria majalis). Disused limestone workings are often colonised by calcareous grassland species whilst quarry ponds may support extensive Charophyte populations (freshwater green algae that are related to modern land plants). Disused acid-rock quarries generally develop a heathland flora including heather (Calluna vulgaris) but may become overwhelmed by gorse (Ulex europaeus).

Limestone quarries are generally of high biodiversity interest and are located all along the outcrop of the Carboniferous Limestone at Pendine, Coygen and between Mynydd-y-Garreg, Meinciau, Crwbin, Mynydd Cerrig, Banc-y-Mansel, Gorswen, Carmel, Pentregwenlais, Cilyrychen and Blaengweche and over Mynydd Du to the county boundary in the east. Several are designated as SSSIs.

Acid gritstone, sandstone, flagstone and clay quarries often also have high biodiversity interest and are scattered throughout the county. Several are located along the Millstone Grit outcrop and there are also several large disused sandstone/clay workings in the Llanelli area. Other large sandstone quarries (some of which have characteristic early-successional floral communities) are located, for example, at Llansawel, between Bronwydd and Cynwyl Elfed, Pontarllechau and south of Lampeter and there is an igneous rock quarry at Llangynog.

Many are also of importance for nesting birds including peregrine, kestrel and raven.

There is scope for sensitive restoration of working quarry sites as they become worked-out.

Former refuse tips

Whilst active refuse tips provide feeding opportunities for birds such as gulls and corvids and also buzzard and red kite and may also be a source of interesting plant records, former refuse tips such as those located at Glynhir, Kidwelly and Pembrey Harbour generally have limited biodiversity value where overgrown vegetation provides habitats for a number of animals and plants. Large populations of small mammals such as voles and shrews provide food for birds such as buzzards, kestrels and owls. Teasels, thistles and other tall herb species provide food for finches whilst their generally open nature attracts breeding birds such as skylark and meadow pipit.

Former metaliferous industrial sites particularly in the Llanelli area

Many of these have now been reclaimed with the loss of their ephemeral (short lived) vegetation and characteristic alien plants, associated fauna and cultural heritage. Some sites have also developed lower-plant interest with the establishment of scarce bryophytes (mosses) and lichens. Particular faunal interest may include bees, wasps, beetles and flies. Those that remain are often eye-sores and scheduled for early re-development.

Railway sites

Several sites of former sidings have developed significant biodiversity interest within the county. Examples are prostrate toadflax (Linaria supina) and small blue butterfly populations around Burry Port Harbour, dittander (Lepidium latifolium) at Pantyffynnon, small toadflax (Chaenorhinum minus) and pale toadflax (Linaria repens) at Carmarthen and yellow-juiced poppy (Papaver dubium ssp. lecoqii) at Morfa, Llanelli. Other disused railway lines have been recolonised by scrub and developing woodland and provide valuable nesting, foraging, roosting and refuge habitats for birds, bats and other fauna as well as wildlife corridors. The verges, cuttings and embankments of extant railway lines are often also of biodiversity importance and are also valuable wildlife corridors.

Many post-industrial sites within Carmarthenshire which had developed into valuable wildlife-rich sites have been lost in recent years. Some of the major losses have been as a result of :

• reclamation of coal spoil in association with opencast,
• new industrial/retail development parks and
• the loss of former industrial and pfa sites as the development of the Llanelli Millennium Coastal Park has proceeded.

Brownfield sites in Carmarthenshire designated as SSSIs include the Pwll (PFA) Lagoon, Machynys Ponds and several limestone quarries, such as those included within Cernydd Carmel SSSI. Several small quarries are also designated as geological SSSIs. The Ashpits Pond between Pwll and Burry Port is a Local Nature Reserve.

Current Factors Affecting the Habitat

• Re-development leading to further fragmentation and loss of habitats and species.
• Lack of awareness by developers and planners of the biodiversity value of sites and of the potential to incorporate and enhance biodiversity as part of any development.
• Use of non-native species in landscaping and planting schemes and conversion of wildlife-rich habitats to amenity grassland or tree planting.
• Decontamination of land of ecological importance. Importation of topsoil and other substrates for remediation, leading to the loss of existing nutrient-poor or chemically restrictive soils, which may be supporting unusual species or communities.
• Damage to sites caused by unmanaged or inappropriate recreational use, e.g. motorbikes; fly tipping and vandalism.
• Accidental or deliberate introduction of non-native (and some native) plant species, which may dominate areas at the expense of native plants (e.g. Japanese knotweed, sea buckthorn, gorse), or contaminate the native gene-pool (e.g. the eastern European sub-species of bird’s-foot trefoil and various grass species).
• Succession of abandoned and neglected sites to closed habitats of lesser value, e.g. scrub, brambles, nettles and other tall ruderal communities.

Gardens and Urban Open Spaces

Over recent years gardens and allotments have become increasingly important habitats for wildlife, including many species now rare in the wider countryside. Gardens and allotments can also be important wildlife corridors. In our towns, a large proportion of available wildlife habitat is provided by gardens, which are the 'green lungs' of our urban environment.

Gardens also play an important role in allowing people to have close contact with nature. Gardeners can also affect wildlife conservation in the wider countryside. However many gardening practices are detrimental from a biodiversity perspective and more work is needed to encourage wildlife-friendly gardening. For example, the use of peat has a detrimental effect on our peatlands habitats.
As the wider environment loses species, gardens provide a refuge for a huge variety of birds and insects. Other species such as hedgehogs and amphibians may now have significant strongholds in urban back gardens.

Allotments can also cover a significant area of land in towns and can therefore make a valuable contribution to the wildlife potential of urban areas. The diversity of habitats found in allotments – cultivated and fallow ground, grassy areas, empty overgrown plots, compost heaps, sheds etc – make them important for a wide range of plants and animals. Allotments offer benefits for the whole community and contribute to the sustainable regeneration of towns and cities, providing green areas in urban environments.

Urban open space is a term used to describe parks, green spaces, and other open areas such as playing fields. They can be highly managed environments or relatively natural areas. They are commonly open to public access.

These areas are important because they offer good recreational opportunities for people, can be islands of nature, promoting biodiversity and providing a habitat for natural species in environments that are otherwise uninhabitable due to city development provide people to get out and enjoy nature in an urban setting.

Current Status in Carmarthenshire

Carmarthenshire’s towns have some good examples of parks and open spaces. Parc Howard in Llanelli  contrasts with the more newly created open space within the Millennium Coastal Park. Betws Park in Ammanford is a good example of formal gardens alongside the natural river habitat and tough grassland at the end of the park. Small settlements have areas of recreational open space containing play sports areas. In Llandeilo Parc Penlan has recently been given Green Flag status and hopefully will start a trend of managing parks for biodiversity as well as more formal recreation.

Current Factors Affecting these Habitats

Many gardens are now paved or decked or, if large, built upon. Loss of this habitat could be significant given the importance of gardens for wildlife. Open urban space is increasing built upon and over management can cause a decline in value for biodiversity.