The color of artificial light affects mate attraction in the common glow-worm

• Published in: The Science of the total environment Vol. 857; p. 159451
• Main Authors: Kivelä, Linnea, Elgert, Christina, Lehtonen, Topi K., Candolin, Ulrika
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.01.2023
• Subjects: Artificial light at night; Environmental change; Lampyridae; Light pollution; Mate choice; Spectral tuning; Spectral tuning; Environmental change; Light pollution; Artificial light at night; Lampyridae; Mate choice
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.159451

Artificial light at night, often referred to as ‘light pollution’, is a global environmental problem that threatens many nocturnal organisms. One such species is the European common glow-worm (Lampyris noctiluca), in which reproduction relies on the ability of sedentary bioluminescent females to attract flying males to mate. Previous studies show that broad-spectrum white artificial light interferes with mate attraction in this beetle. However, much less is known about wavelength-specific effects. In this study, we experimentally investigate how the peak wavelength (color) of artificial light affects glow-worm mate attraction success in the field by using dummy females that trap males landing to mate. Each dummy was illuminated from above by either a blue (peak wavelength: 452 nm), white (449 nm), yellow (575 nm), or red (625 nm) LED lighting, or light switched off in the control. We estimated mate attraction success as both the probability of attracting at least one male and the number of males attracted. In both cases, mate attraction success depended on the peak wavelength of the artificial light, with short wavelengths (blue and white) decreasing it more than long wavelengths (yellow and red). Hence, adjusting the spectrum of artificial light can be an effective measure for mitigating the negative effects of light pollution on glow-worm reproduction. [Display omitted] •Light pollution is an emerging environmental threat to nocturnal organisms.•Glow-worms are dependent on darkness for mate finding.•Dummy female glow-worms were exposed to four colors of light in the field.•Long wavelength artificial light was less detrimental to mate attraction success.•Spectral tuning of outdoor lighting is a potential mitigation measure.