Basics
- Event/Issue: A global study (covering 583 bird species, 60 million vocalisations) found that artificial light at night extends birds’ daily activity by up to an hour.
- Background: Light pollution disrupts circadian rhythms, migration, feeding, and breeding cycles of animals.
- Fact: In brightly lit areas, birds remain active ~50 minutes longer after sundown compared to darker areas.
Relevance:
- GS-III: Environment (Pollution, Biodiversity Conservation, Urban Ecology).
- GS-II: Polity (Right to clean environment under Article 21).

Why in News
- Published research led by Southern Illinois University and Oklahoma State University shows how artificial light alters bird behaviour globally.
- Data was analysed using BirdWeather and AI tool BirdNET, creating the largest global acoustic database on bird activity.
Significance
- Ecological: Impacts bird migration, breeding success, and food chain balance.
- Policy relevance: Highlights emerging dimension of pollution beyond air, water, noise.
Overview
Polity/Legal
- No specific legislation on light pollution in India; falls indirectly under Environment Protection Act (1986) and local municipal bye-laws.
- SC in several judgments (e.g., noise pollution) recognised right to a clean environment under Article 21—possible extension to light pollution.
Governance/Administrative
- Urban planning and smart cities must integrate “dark-sky compliant” lighting.
- Municipal bodies regulate streetlights, advertising hoardings, and glass facades but lack ecological guidelines.
Economy
- Excessive lighting increases energy consumption and costs.
- Light pollution affects tourism (e.g., dark-sky tourism in Ladakh, Madhya Pradesh).
Society
- Human health impact: disrupted circadian rhythm, sleep disorders, lifestyle diseases.
- Cultural impact: diminishing night sky visibility reduces connection with natural heritage.
Environment/Science & Tech
- Disturbs wildlife: birds, insects (fireflies), bats, turtles.
- Alters ecological processes like pollination and predator-prey dynamics.
- Satellite mapping of light pollution can guide mitigation.
International
- International Dark-Sky Association (IDA) sets global standards.
- Countries like France and South Korea regulate outdoor lighting.
- India not yet part of international “dark-sky reserves” movement beyond local initiatives.
Challenges
- Lack of legal recognition of light pollution as an environmental threat.
- Urban bias in data (most studies from Global North).
- Balancing safety/security needs with ecological concerns.
- Low public awareness compared to air or water pollution.
- Weak inter-agency coordination (urban development, power, environment).
Way Forward
- Legal framework: Include light pollution under Environment Protection Rules; mandate impact assessments.
- Dark-sky policies: Adopt IDA’s best practices—shielded streetlamps, reduced intensity, smart timers.
- Technology: Use motion-sensor LEDs, adaptive lighting, GIS mapping of hotspots.
- Awareness campaigns: Public outreach like Earth Hour; integrate into school curricula.
- Research & Data: Expand monitoring in Global South (India’s rich bird diversity).
- Global SDG link: Contributes to SDG 11 (Sustainable Cities) and SDG 15 (Life on Land).
Conclusion
Light pollution is a reversible environmental threat, unlike climate change or deforestation. With low-cost interventions and community participation, India and the world can restore the natural balance of night for both humans and wildlife.