Data from: Street lighting: sex-independent impacts on moth movement

1.Artificial lights have become an integral and welcome part of our urban
and peri-urban environments. However, recent research has highlighted the
potentially negative ecological consequences of ubiquitous artificial
light. In particular, insects, especially moths, are expected to be
negatively impacted by the presence of artificial lights. Previous
research with light traps has shown a male-biased attraction to light in
moths. 2.In this study, we sought to determine if street lights could
limit moth dispersal and if there was any sex bias in attraction to light.
More specifically, we aimed to determine sex specific attraction radii for
moths to street lights. 3.We tested these hypotheses by collecting moths
for two years at an experimental setup. To estimate the attraction radii
we developed a Markov model and related it to the acquired data.
4.Utilizing multinomial statistics, we found that attraction rates to
lights in the middle of the matrix were substantially lower than predicted
by the null hypothesis of equal attraction level (0.44 times). With the
Markov model, we estimated that a corner-light was 2.77 times more
attractive than a wing-light with an equivalent attraction radius of c.
23m around each light. We found neither sexual differences in the
attraction rate nor in the attraction radius of males and females. Since
we captured three times more males than females, we conclude that sex
ratios are representative of operational sex ratios or of different flight
activities. 5.These results provide evidence for street lights to limit
moth dispersal, and that they seem to act equally on male and female
moths. Consequently, public lighting might divide a suitable landscape
into many small habitats. Therefore, it is reasonable to assume i) that
public lighting near hedges and bushes or field margins reduces the
quality of these important habitat structures, and ii) that public
lighting near important habitat structures but not interfering with local
movement may affect moth movement between patches.