There are both direct and indirect impacts on biodiversity from transport. The growth of roads is particularly significant; road construction can damage, fragment or result in the complete loss of habitats, and also act as barriers to species movement. Lighting associated with roads can adversely affect bat populations and other work such as bridges can affect BAP species such as bats, otters and shad. Extraction from gravel pits and quarries of aggregates for road building can have significant effects on wildlife. Car travel has increased dramatically in recent decades and is forecast to continue growing.

Upgrading of the road network has the potential to adversely effect wildlife and it is important that each project does not damage important habitats. Transport also makes a substantial contribution to greenhouse gas emissions and acid rain.  

The verges adjacent to raods and railways can provide valuable habitat areas for our wildlife and are often remants of semi-natural habitats that were once much more widespread in the county. However, even newer verges can be surprisingly rich. These verges provide habitats for small mammals, birds and insects and act as wildlife corridors along which species can move.

Carmarthenshire County Council has produced a Local Transport Plan covering 2001-2006 to address some of the transport issues referrred to above.

In addition the National Assembly for Wales, having direct responsibilty for the maintenance, improvement and development of the trunk road and motorway network of Wales, has produced a Trunk Road Estate Biodiversity Action Plan , which recognises the biodiversity interest of these roads and has objectives including ones to increase awareness of the Transport Directorate's staff and contractors, its environmental partners and the general public, of the biodiversity interest of the road network and to encourage the use, and dissemination of the best practice for biodiversity in the management and development of the network.