Multiple night‐time light‐emitting diode lighting strategies impact grassland invertebrate assemblages. (31st January 2017)

• Record Type: Journal Article
• Authors: Davies, Thomas W.; Bennie, Jonathan; Cruse, Dave; Blumgart, Dan; Inger, Richard; Gaston, Kevin J.
• Is Part Of: Global change biology. Volume 23:Number 7(2017)
• Page Start: 2641
• Page End: 2648
• Publication Date: 2017-01-31
• Subjects: artificial light at night -- beetles -- grassland -- invertebrates -- light‐emitting diodes -- light pollution -- spiders; Climatic changes -- Environmental aspects -- Periodicals; Troposphere -- Environmental aspects -- Periodicals; Biodiversity conservation -- Periodicals; Eutrophication -- Periodicals; 551.5
• DOI: 10.1111/gcb.13615
• Languages: English
• ISSNs: 1354-1013

Abstract

Abstract: White light‐emitting diodes (LEDs) are rapidly replacing conventional outdoor lighting technologies around the world. Despite rising concerns over their impact on the environment and human health, the flexibility of LEDs has been advocated as a means of mitigating the ecological impacts of globally widespread outdoor night‐time lighting through spectral manipulation, dimming and switching lights off during periods of low demand. We conducted a three‐year field experiment in which each of these lighting strategies was simulated in a previously artificial light naïve grassland ecosystem. White LEDs both increased the total abundance and changed the assemblage composition of adult spiders and beetles. Dimming LEDs by 50% or manipulating their spectra to reduce ecologically damaging wavelengths partially reduced the number of commoner species affected from seven to four. A combination of dimming by 50% and switching lights off between midnight and 04:00 am showed the most promise for reducing the ecological costs of LEDs, but the abundances of two otherwise common species were still affected. The environmental consequences of using alternative lighting technologies are increasingly well established. These results suggest that while management strategies using LEDs can be an effective means of reducing the number of taxa affected, averting the ecological impacts of night‐time lighting may ultimately require avoiding its use altogether. Abstract : White light‐emitting diodes (LEDs) are rapidly replacing conventional outdoor lighting around the world, despite rising concerns over their effects on animals and plants. We compared the efficacy with which alternative lighting strategies reduced the number of ground‐dwelling invertebrate taxa aggregating under LEDs. A combination of dimming by 50% and switching lights off between midnight and 04:00 am showed the most promise for reducing the ecological impacts of LEDs, but did not avoid them altogether. Averting the environmental consequences of LEDs and other lighting technologies may ultimately require avoiding their use altogether.