DOI: 10.5061/dryad.6djh9w1d2
title: Data from: Skyglow and especially direct streetlight pollution alter moth communities

description: Light pollution caused by artificial light at night (ALAN) affects
 biodiversity worldwide and is still increasing. Species vary in their
 response to ALAN, but the impact on communities remains poorly understood.
 Effects of indirect light pollution by skyglow and direct streetlight
 pollution on communities have usually been addressed separately, and in
 most studies so far, urbanisation levels are a confounding factor for ALAN
 effects per se. Here, we sampled garden moth communities according to a
 study design that integrated two levels of direct streetlight pollution
 and two regional skyglow levels to test for additive effects of both types
 of ALAN. We also tested whether ALAN conditions related to community
 changes in species’ morphological, behavioural and life-history traits.
 Both skyglow and streetlights negatively affected moth abundance. Species
 richness and diversity decreased under direct streetlight, independent of
 skyglow levels. Both types of ALAN affected moth community composition,
 and we identified several relationships with species traits in the local
 moth communities. Skyglow filtered for hibernating stage and larval
 habitation, while streetlight pollution filtered for voltinism, larval
 food specificity, habitat openness, and hibernating stage. Our study
 provides evidence that both skyglow and, more strongly, streetlight
 pollution affect moth communities. A significant decline in moth abundance
 will have consequences for ecosystem functioning through reduced food
 availability for predators and diminished pollinator services. At the
 community level, ALAN operates as a filter for species and species traits,
 and based on our results, we argue that future studies should consider
 both skyglow and direct light pollution.
description: # Data from: Skyglow and especially direct streetlight pollution alter
 moth communities Dataset DOI:
 [10.5061/dryad.6djh9w1d2](10.5061/dryad.6djh9w1d2) ## Description of the
 data and file structure The dataset "EVdS et al-EnvPol.xlsx"
 contains: moth abundance data from gardens under different skyglow levels
 and with or without nearby streetlights; environmental data for each
 garden; moth species traits. Moths were sampled in collaboration with
 citizen scientists, using both light and bait traps. Light trapping took
 place on pre-defined nights; moths were photographed by the volunteers
 ,and moths were identified by the first author using local literature.
 Bait traps remained continuously active for several days; trapped moths
 were collected by the authors and identified using local literature and
 moth genitalia examination. All missing data given as NA. ### Files and
 variables #### File: EVdS\_et\_al-EnvPol.zip **Description:** This dataset
 contains all data used for our analyses in the R-script ("EVdS et
 al-EnvPol.R"). It contains: moth abundance data per sampling;
 environmental data for each garden; species trait data. **Sample:** Moth
 abundance data for each individual sampling. **Trap:** Pooled abundance
 data per garden per trap type. **Site:** Pooled abundance data per garden.
 **LedBait:** Pooled abundance data per trap type. **Cond:** Pooled
 abundance data per light pollution condition per trap type.
 **FMSample:** Abundance data for each individual sampling; for species
 trait analysis. **FMSample01**: Presence/absence data for each individual
 sampling; for species trait analysis. **Trait:** Species trait data
 Variables abundance/presence-absence data: * Skyglow: skyglow level at
 sampling site. Low = low-medium; high = high-medium. * SL: Yes = nearby
 streetlight present; No = no nearby streetlight. * SQM: Sky Quality Meter
 (mag./arc sec²). * NearestSL: distance between sampling site and nearest
 streetlight (m). * Trap: trap type. * Day: day of the year sampling took
 place (light trap) or began (bait trap). * SL400: number of streetlights
 within 400 m of the sampling site. * BA400: built-up area within 400 m of
 the sampling site (%). * Area: garden area (m²). * Forest400: forested
 area within 400 m of the sampling site (m²). Variables trait data: * Spec:
 scientific species name. * Species: abbreviation species name. * Family:
 moth family. * FWL: mean forewing length (mm). * FWLmin: minimal forewing
 length (mm). * FWLmax: maximal forewing length (mm). (For the following
 variables, 1 = yes; 0 = no) * Monov: monovoltine. * Biv: bivoltine. *
 Multiv: multivoltine. * Cover: prefered habitat openness. * Hibern:
 hibernation stage. * Larva: larval habitation. * Monoph: monophagous. *
 Oligoph: oligophagous. * Polyph: polyphagous. * AdultTwilight: adult
 active at twilight. #### File: EVdS\_et\_al-EnvPol.R * Packages: readxl,
 vegan, car, effects, lme4, lmerTest, BAT, ggplot2, ggthemes, gridExtra,
 egg, ggeffects, ggbiplot, blmeco, emmeans, ggVennDiagram * Functions: *
 sumSE: function to calculate group means and standard errors. These are
 also used to produce the graphs. * Size...: funcions to set figure sizes.
 * Statistical tests: * Environment ~ Treatment: test to verify whether
 environmental variables differ between light pollution conditions. *
 Diversity: test differences in diversity measures between light pollution
 conditions. * perManova: perManova to test differences in community
 composition between light pollution conditions. * NMDS: visualisation of
 differences in community composition between light pollution conditions. *
 CWM: test differences in community-weighted means of moth species
 traits between light pollution conditions. * Figures: contains the script
 to produce the graphs.