Avoid illumination of bat foraging, drinking and swarming sites

Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
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How is the evidence assessed?

Effectiveness

72%
Certainty

35%
Harms

0%

Calculating overall effectiveness category

Background information and definitions

Key bat habitats such as foraging, drinking and swarming sites should be left unlit to avoid disturbance to bats. Dark buffer zones may also be retained around them.

Source countries

Key messages

One study evaluated the effects of avoiding the illumination of key bat habitats on bat populations. The study was in Italy.

COMMUNITY RESPONSE (0 STUDIES)

POPULATION RESPONSE (1 STUDY)

Abundance (1 study): One replicated, randomized, before-and-after study in Italy found that unlit water troughs had greater activity (relative abundance) of five of six bat species/species groups than troughs illuminated with artificial light.

BEHAVIOUR (0 STUDIES)

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

A replicated, randomized, before-and-after study in 2015 of four cattle troughs within forest in central Italy (Russo et al. 2017) found that unlit troughs had higher drinking activity for five of six bat species/species groups than troughs illuminated with artificial light. More drinking buzzes were recorded for five bat species/species groups when troughs were unlit than when they were illuminated with artificial light: barbastelle bat Barbastella barbastellus (unlit: 584; lit: 306), brown long-eared bat Plecotus auritus (unlit: 78; lit: 0), Myotis spp. (unlit: 599; lit: 134), Kuhl’s pipistrelle Pipistrellus kuhlii (unlit: 116; lit: 64) and Savi’s pipistrelle Hypsugo savii (unlit: 39; lit: 10). For the common pipistrelle Pipistrellus pipistrellus, the difference was not significant when troughs were unlit (240 drinking buzzes) or illuminated (165 drinking buzzes). Each of four cattle troughs consisted of two troughs (6 x 1.5 m) joined together. Troughs were illuminated with a portable LED (light-emitting diode) white light (average 49 lux). Each of four sites was surveyed using bat detectors on two nights with five randomized lit and unlit 10 minute intervals/night in July–August 2015.
Study and other actions tested
Referenced paper
Russo D., Cistrone L., Libralato N., Korine C., Jones G. & Ancillotto L. (2017) Adverse effects of artificial illumination on bat drinking activity. Animal Conservation, 20, 492-501

Please cite as:

Berthinussen, A., Richardson O.C. and Altringham J.D. (2019) Bat Conservation. Pages 67-140 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

This Action forms part of the Action Synopsis:

Bat Conservation

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