The effect of artificial light at night on nocturnal mammals

Surface area lit by artificial light at night increases by 2 percent each year. In this project we investigate how nocturnal animals such as bats respond to the illumination and which solutions we can offer to mitigate or compensate the potentially detrimental effects of light pollution on bats. 

Project details
Duration: since 01/2008
Third-party funded: yes
Involved Department(s): Dept Evolutionary Ecology, Dept Evolutionary GeneticsDept Ecological Dynamics
Leibniz-IZW Project Leader(s): Christian Voigt (Dept Evolutionary Ecology)
Leibniz-IZW Project Team: Daniel Lewanzik (Dept Evolutionary Ecology), Camila Mazzoni (Dept Evolutionary Genetics), Stephanie Kramer-Schadt (Dept Ecological Dynamics)
Consortium Partner(s): University of Potsdam, Technical University of Berlin,
Uwe Hoffmeister, Tobias Teige and Torsten Blohm (expert’s offices, Berlin and Brandenburg), Max-Planck-Institute for Ornithology (Seewiesen)
Current Funding Organisation: Various funding agencies, including the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, the Federal Ministry of Education and Research (BMBF, BIBS), the German Research Foundation (DFG, Biomove Research Training Group)
Research Foci: Understanding traits and evolutionary adaptations
Understanding wildlife health and disturbed homeostasis
Understanding the environmental context
Improving population viability


Each year, the relative proportion of the earth’ surface illuminated by artificial light at night is increasing by 2 percent. Since many of our wildlife species are nocturnal, they are exposed to an increasing level of artificial illumination in their habitats. Additionally, we are facing a highly dynamic transition of outooor lighting schemes (e.g. LED), which happens without knowing how these new light types might impact plants, animal and whole ecosystems.

Bats are obligatory nocturnal mammals, which have evolved over millions of years to cope with a life in darkness. Bats use echolocation to orientate at night and to find food. Among native bats some are exploiting insects at street lanterns in an opportunistic way, others respond very aversively towards artificial light at night.

We examine on the individual, population and landscape level how bats react to artificial light at night. We are doing this by studying bats in different contexts; for example, we observe how bats respond to artificial light when emerging from their roosts or when hunting or commuting.

Conservation related findings are communicated via workshops, conferences and guidelines, to specific stakeholders and to the general public.

Our collaborators in Berlin and Brandenburg help us in conducting field work and in analysing the spatio-temporal movements of bats.

Applied methods comprise field work on the effect of artificial light at night on the habitat use of bats (Department Evolutionary Ecology), analysis of movement paths (Department Ecological Dynamics), the analysis of the degree of kinship of socially migrating bats (Deptartment of Evolutionary Genetics). External cooperation partners are the EUROBATS secretariat and the Max Planck Institute for Ornithology (Seewiesen).

Selected Publications

Straka TM, Greif S, Schultz S, Goerlitz H, Voigt CC (2020): The effect of cave illumination on bats. GLOBAL ECOL CONSERV 21. doi:10.1016/j.gecco.2019.e00808.

Voigt CC, Scholl J, Bauer J, Teige T, Yovel Y, Kramer-Schadt S, Gras P (2020): Movement responses of common noctule bats to the illuminated urban landscape. LANDSCAPE ECOL 35, 189-201. doi:10.1007/s10980-019-00942-4.

Straka T, Wolf M, Gras P, Buchholz S, Voigt CC (2019): Tree cover mediates the effect of artifical light on urban bats. FRONT ECOL EVOL. Doi:10.3399/fevo.2019.00091.

Voigt CC, Azam C, Dekker J, Ferguson J, Fritze M, Gazaryan S, Hölker F, Jones G, Leader N, Lewanzik D, Limpens HJGA, Mathews F, Rydell J, Schofield H, Spoelstra H, Spoelstra K, Zagmajster M (2018): Guidelines for consideration of bats in lighting projects. UNEP/EUROBATS publication series #8.

Roeleke M, Teige T, Hoffmeister U, Klingler F, Voigt CC (2018): Aerial-hawking bats adjust their use of space to the lunar cycle. MOV ECOL 6, 11.

Lewanzik D, Voigt CC (2017): Transition from conventional to LED street lighting changes activity of urban bats. J APPL ECOL 54, 264-271.

Voigt CC, Lewanzik D (2011): Trapped in the darkness of the night: Thermal and energetic constraints of daylight flight in bats. PROC ROY SOC B – BIOL SCI 278, 2311-2317.