For example, some bird species may be affected by noise and others by movement. However, different species display a range of tolerances to such disturbance, and valuable habitats can be maintained even next to very busy roads. The design and management of roadside planting can help reduce such effects. Typically, belts of scrub can be used to provide shelter for birds using adjacent wetland habitats. Road crossing Certain species, such as badgers, otters, deer, hedgehogs and amphibians, are at risk from being run over when attempting to cross roads.
Larger animals can also present a safety hazard to traffic.
Measures can be taken either to deter animals from crossing at dangerous locations or to help them cross at more suitable points. For example, underpasses or bridges can be provided at locations where badgers regularly cross a busy road. The following general objectives apply to the whole Scottish trunk road network. Adopt practices which help to maintain and enhance the biological resource. Use native tree species wherever they can effectively fulfil the requirements of the landscape design and management strategy.