Light Pollution and Animal Welfare

Artificial light at night disrupts the behaviour, physiology and welfare of vast numbers of animals by interfering with their light-dependent biological systems.

Key Facts

Light pollution affects an estimated 23% of the Earth's land surface significantly
Migratory birds collide with lit buildings by the hundreds of millions in North America annually
Sea turtle hatchlings are disorientated by beach lighting, crawling toward lights rather than the sea
Insects are attracted to artificial light, causing exhaustion, dehydration and predation
Night-time light suppresses melatonin in nocturnal mammals, disrupting sleep and immune function

Welfare Considerations

Light pollution causes individual welfare harm across multiple taxa — exhausted insects dying around artificial lights, disoriented hatchling turtles crawling miles from the sea, birds flying into lit glass towers, nocturnal mammals unable to find food or mates in bright nights. These are not abstract population effects but direct suffering at individual level at enormous scale. Simple interventions — shielded downward-pointing lights, lights-out programmes during migration — can dramatically reduce harm.

What You Can Do

Switch to shielded, downward-pointing lights that minimise light spill into the sky
Support lights-out programmes during spring and autumn migration seasons in your area
Dim or turn off non-essential exterior lighting between 11 PM and sunrise
Advocate for dark sky ordinances and light pollution control in urban planning