Use shielded “full cut-off” lights to remove outwards lighting

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

  • One study evaluated the effects on butterflies and moths of using shielded “full cut-off” lights to remove outwards lighting. This study was in Slovenia.




  • Behaviour change (1 study): One replicated, paired, controlled study in Slovenia found that fewer individual moths and moth species were attracted to lights fitted with blinds to prevent light scattering (along with filters to remove shorter wavelengths) than to conventional lights without blinds or filters.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A replicated, paired, controlled study in 2011–2013 in 15 churches in Slovenia (Verovnik et al. 2015) found that lights with blinds to prevent light scattering, which were also colour-filtered, attracted fewer individuals and species of moths than conventional lighting. On church walls illuminated with yellow or blue light with blinds, both the abundance (12–20 individuals/year) and species richness of moths (10–15 species/year) were lower than on walls illuminated with conventional lighting and no blinds (abundance: 73 individuals/year; richness: 42 species/year). Fifteen churches in dark, rural areas were grouped into adjacent triplets, and illuminated in one of three ways: blue or yellow metal halide lamps, or the existing light (metal halide or sodium vapour, 70–400 W). Experimental lamps were 70 or 150 W, had custom-made filters to remove wavelengths shorter than 400 nm (blue) or 470 nm (yellow), and blinds to prevent the scattering of light away from the building. The illumination used on each church was rotated within each triplet each year. From May–September 2011–2013, moths were counted for 45 minutes six times/year within a 10 × 3 m area of wall on each church. Churches within a triplet were surveyed on the same night.

    Study and other actions tested
Please cite as:

Bladon A.J., Bladon, E. K., Smith R.K. & Sutherland W.J. (2023) Butterfly and Moth Conservation: Global Evidence for the Effects of Interventions for butterflies and moths. Conservation Evidence Series Synopsis. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

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Butterfly and Moth Conservation

This Action forms part of the Action Synopsis:

Butterfly and Moth Conservation
Butterfly and Moth Conservation

Butterfly and Moth Conservation - Published 2023

Butterfly and Moth Synopsis

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