Artificial light colour temperature influences bat activity patterns in subterranean communities: evidence from disused tunnels
Year: 2026
Type: article
Abstract: Artificial lighting is a growing threat to nocturnal wildlife, yet its impacts in subterranean habitats remain poorly understood. Across the UK, over 650 disused railway tunnels provide important habitat for bats, supporting multiple ecological functions throughout their life cycle. Many tunnels are now being reopened for public access and lit for safety, reflecting a wider global trend of underground tourism. We investigated bat responses to lighting in disused tunnels in southern England and Wales using acoustic monitoring to compare bat activity under white, amber and red light with darkness. A total of 13,128 bat passes were recorded across eight species. Bat activity varied spatially within tunnels, with activity greatest at tunnel entrances, where lighting effects were also most apparent. Separate species-level analyses suggested contrasting patterns of activity across lighting treatments: P. pipistrellus showed no detectable change in activity under any lighting treatment, whereas P. pygmaeus showed reduced activity under red and amber light at the tunnel entrance. Myotis spp. showed reduced activity under white light, while activity under amber and red light did not differ from darkness. No single colour temperature consistently minimised impacts across the taxa examined. These findings suggest that lighting management in bat-occupied tunnels should not rely on a single “bat-friendly” spectrum. Where lighting is necessary, retaining dark areas around tunnel entrances may reduce potential impacts. Site-specific ecological surveys of species composition, spatial use and seasonal activity should inform the design and management of lighting in subterranean habitats.
Source: Biological Conservation
Institutions: University of Bath, Bat Conservation Trust
Language: English
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,830
OpenAlex ID: W7214713834