Bats and Lighting
Lighting can have a harmful effect on bats impacting on their use of a roost and also their commuting routes and foraging areas. Light falling on a roost access point is likely to delay bats from emerging and thereby shorten the amount of foraging time available to them, which is especially damaging around emergence time as that is when there is a peak in the number of insects. In the worst case scenario, it can cause the bats to desert the roost.
Bats and their roosts are all protected by law and bats should always be taken into account when lighting is being considered.
Guidance for Bat Workers and Lighting Engineers
BCT has been working with the Institution of Lighting Engineers (ILE) to produce 'Bats and Lighting in the UK', an online document suitable for both bat workers and lighting engineers. It is now available as Version 3 and it is expected to undergo further updates as knowledge from ongoing bat research and changes in lighting technology develop.
What else are we doing?
BCT is working with other wildlife groups affected by artificial lighting to establish if the mitigation suggested in the bats and lighting document is suitable for their concerns too or if it could be made suitable with some additional text. This collaborative approach is proving most helpful as it helps to raise awareness to a greater audience.
At the end of 2007 the Royal Commission on Environmental Pollution (RCEP) made it known that they are undertaking a short study on artificial light and the environment. BCT has been fully involved in the consultation process and from the suite of possible areas on which the study could have concentrated, the decision has been made to focus this study on the effects on health and wildlife. The resultant document is expected to be published in 2009.
As more bat workers have access to light meters, the National Bat Monitoring Programme colony counts now allow the opportunity to include information about the lux levels measured during bat emergence. Those carrying out NBMP car surveys are being asked to record the type of street lighting along their route. All this data being gathered will be important in identifying trends that will support current research.
News
On 27 November 2009 the Royal Commission on Environmental Pollution (RCEP) published the long-awaited report entitled 'Artificial Light in the Environment'. The report addresses two issues - the effect of artificial light on amenity and the possibility of nuisance being caused by badly designed or inappropriate lighting and, of great interest, the possible effects of artificial light on nature and eco-systems. Although the report covers some aspects of the impacts on wildlife with brevity that can lead to a slightly diluted set of information, the set of recommendations are worthwhile. The lighting industry is already (January 09) holding workshops to review the implications of the report and ways in which to act on the recommendations. BCT was consulted as part of the preparation for this publication and are now represented in the resultant discussions on carrying this matter forward.
Other useful websites
Lighting
Institution of Lighting Engineers
Wildlife organisations
Royal Society for the Protection of Birds
Research
Related downloads
A basic introduction to the legal protection of bats in the British Isles.
Basic advice for developers, planning officers and others who come across bat issues in the context of the English planning system.