Street lighting changes the composition of invertebrate communities

Abstract

Artificial lighting has been used to illuminate the nocturnal environment for centuries and continues to expand with urbanization and economic development. Yet, the potential ecological impact of the resultant light pollution has only recently emerged as a major cause for concern. While investigations have demonstrated that artificial lighting can influence organism behaviour, reproductive success and survivorship, none have addressed whether it is altering the composition of communities. We show, for the first time, that invertebrate community composition is affected by proximity to street lighting independently of the time of day. Five major invertebrate groups contributed to compositional differences, resulting in an increase in the number of predatory and scavenging individuals in brightly lit communities. Our results indicate that street lighting changes the environment at higher levels of biological organization than previously recognized, raising the potential that it can alter the structure and function of ecosystems.

Out of the Dark: Establishing a Large-Scale Field Experiment to Assess the Effects of Artificial Light at Night on Species and Food Webs

“…Further recordings of insect catches during the next years will enable us to quantify the loss of biomass and to detect a change in the composition of orders and species. Composition changes have only recently been observed at established street lights [32], emphasizing the need for a detailed analysis of the catches and the impacts of introduced street lights in this ecosystem. Thereby, the accompanying observations of movement behavior and foraging of birds and bats might add to the study.…”

“…Apart from two recent long-term experimental illumination studies that included several generations of key species [26,27], the effects of ALAN have only been studied in laboratory experiments (e.g., [15,28]) or by making observations at or near existing public light infrastructure [29][30][31][32]. The limitations of these approaches include an inability to predict community-and ecosystem-level effects from laboratory experiments, and the potentially confounding effect of studying communities of organisms that are already accustomed to the presence of ALAN [12].…”

Artificial Light at Night Affects Organism Flux across Ecosystem Boundaries and Drives Community Structure in the Recipient Ecosystem

“…Conversely, ALAN appeared to affect the composition of ground-dwelling arthropods, with some evident taxa-specific responses. Pachygnatha clercki, Lycosidae spiders and Opiliones (harvestmen) were more abundant in lit sites, likely attracted by the increased prey availability around the lamps (Davies et al, 2012). Meyer and Sullivan (2013) reported a reduction in the abundance of Tetragnathidae spiders in illuminated locations.…”

“…The attraction of terrestrial insects to ALAN light sources is well-documented (Eisenbeis et al, 2006) and it can have negative consequences (Horváth et al, 2009;Perkin et al, 2014a;Degen et al, 2016). Most research has focused on individual species, although there have been a few studies examining communities (e.g., Davies et al, 2012;Hölker et al, 2015;Holzhauer et al, 2015;Spoelstra et al, 2015;Grubisic et al, 2017), ecosystem functions (Knop et al, 2017) and ecosystems (Gaston et al, 2015).…”

European Wilderness in a Time of Farmland Abandonment

“…Light pollution has been decried for its impact on the visibility of the natural night sky (Cinzano et al 2000), diminishing the night wilderness experience. But artificial light has also strong ecological impacts (Longcore and Rich 2004;Navara and Nelson 2007;Hölker et al 2010b;Gaston et al 2013), affecting invertebrates (Davies et al 2012, see Chap. 6), fish (Becker et al 2013), mammals (Boldogh et al 2007) and bird populations (Montevecchi et al 2006).…”