Light Pollution Impacting Biodiversity

General Studies Paper-3

In News

• A recent global study has found that artificial light at night is significantly altering bird behaviour, causing many species to stay active for up to an hour longer after sunset.

What Is Light Pollution?

• Light pollution refers to the excessive or inappropriate use of artificial outdoor lighting, which disrupts natural darkness.
• It disrupts ecosystems, obscures the night sky, and affects human health and energy efficiency.

Causes

• Urbanisation: Expansion of cities leads to more streetlights, billboards, and building illumination.
• Over use: Use of artificial lighting beyond what is necessary, especially in commercial zones and residential areas.
• Increase in commercial Activity: Bright signage and lighting in malls, petrol stations, and industrial zones contribute significantly.
• Unregulated Use of LEDs: While energy-efficient, high-intensity LEDs often emit blue light, which scatters more in the atmosphere.

Impacts

• Environmental and Ecological: Nocturnal animals, migratory birds, and insects rely on natural light cycles.
  • Birds living in brightly lit areas tend to sing earlier at dawn and later at dusk, disrupting their natural rhythms and negatively impacting migration, feeding, and breeding patterns.
  • Similar effects occur in species like fireflies, whose communication suffers. Artificial lighting confuses navigation and feeding patterns.
  • Altered light exposure affects flowering and photosynthesis cycles of Plant Growth.
• Human Health: Exposure to artificial light at night suppresses melatonin production, leading to insomnia and other health issues.
  • Chronic exposure to light pollution has been linked to increased stress and reduced cognitive performance.
• Astronomy and Scientific Research: Brightening of the night sky hampers astronomical observations, especially near urban centers.
• Energy Waste: Billions of units of electricity are wasted annually due to poorly directed lighting, increasing carbon emissions.

Suggestions and Way Forward

• Light pollution is a rising issue that harms health, environment, and connection to the night sky.
• In urban planning, adopting Dark Sky-compliant lighting and enforcing zoning regulations can reduce unnecessary illumination, especially in residential and ecologically sensitive areas.
• Governments should strengthen the implementation of national lighting codes and incentivize smart lighting systems like motion sensors and timers.
• Public engagement through citizen science initiatives and integrating light pollution topics into educational curricula can raise awareness.