Light Pollution and Wildlife Welfare

Artificial light at night disrupts natural biological rhythms, navigation, and behaviour in a wide range of wildlife species, causing welfare harms and population-level impacts.

Key Facts

Artificial light at night is estimated to affect the physiology of up to 30% of vertebrate species
Migratory birds attracted to lit structures collide with buildings at much higher rates
Sea turtle hatchlings navigating by starlight are disoriented by coastal artificial light
Light pollution disrupts melatonin production and circadian rhythms in mammals including deer and bats
Insect populations near artificial lights show significant mortality and disrupted foraging behaviour

Welfare Considerations

Light pollution is an underappreciated source of wildlife welfare harm that operates across ecological communities including migratory birds, sea turtles, bats, insects, and mammals. Unlike many environmental stressors, artificial light at night operates around the clock and across seasons, making it a persistent chronic stressor. Disruption to circadian rhythms affects sleep, hormonal regulation, immune function, and reproductive timing in affected wildlife. For migratory species, disorientation by artificial light can prove fatal through collision or energy-depleting route disruption. The good news is that light pollution is technologically tractable: directional lighting, motion sensors, low-spectrum lighting, and night-sky darkness zones all reduce impacts significantly.

What You Can Do

Reduce unnecessary outdoor artificial lighting on your property at night
Choose downward-pointing, warm-spectrum lighting that minimises light scatter
Support dark sky reserve designation and light pollution regulations in your area
Advocate for bird-safe building design standards that reduce collision risk
Support research into the welfare impacts of light pollution on diverse wildlife species