Light Pollution and Bat Welfare | Animal Welfare Hub

Artificial light at night disrupts bat foraging, commuting routes, and roost sites, causing welfare harm to species that evolved to exploit darkness for survival.

Key Facts

Light pollution has increased by 2% annually globally over the past decade
Light-sensitive bat species including horseshoe bats avoid illuminated areas entirely, fragmenting their habitat
Insects, the primary prey of bats, are killed in vast numbers by artificial lights, reducing food availability
Light spill into bat roost entrances delays emergence and reduces foraging time
Low-intensity amber LED lighting is less disruptive to bats than white or blue-spectrum lights

Welfare Considerations

Bats evolved over millions of years to exploit the ecological niche of darkness. Artificial light at night fundamentally disrupts this niche: light-sensitive species cannot use illuminated areas for foraging or commuting, fragmenting their habitat. Light near roosts delays emergence, reducing feeding time and individual condition. The loss of insect biomass to artificial lights compounds the problem by reducing food availability. Responsible lighting — directed downward, using amber spectrum, turned off when not needed — significantly reduces harm to bats and other nocturnal wildlife.

What You Can Do

Switch outdoor lighting to amber spectrum LEDs and use motion sensors to minimise on-time
Advocate for dark sky policies in your local area including council lighting upgrades
Support local bat groups that monitor population responses to light mitigation measures
Report light spill near known bat roosts to developers and local authorities
Learn to recognise bat species in your area and their sensitivity to light pollution