Light pollution is excessive, poorly directed or inappropriate artificial light at night that alters natural darkness. In coastal areas, light pollution typically comes from street lighting, foreshore amenities, ports and marinas, car parks, sporting fields, promenades, private residences and temporary event infrastructure.

It can include:

• light that spills outside the area intended to be lit
• overly bright light or glare that reduces visibility
• scattered light that brightens the night sky
• inappropriate light spectrum, such as blue wavelengths that most strongly affects wildlife.

Light pollution is an emerging environmental pressure in coastal areas, especially because it interacts with additional stressors of climate change, urban growth and increasing night‑time use of coastal areas.

For many marine and coastal species, natural darkness and light intensities and moon phase can be important for ecological and biological processes. Artificial light can disrupt orientation, feeding, breeding and migration.

Documented impacts from DCCEEW include the list below.

Artificial lighting on or near nesting beaches can disorient adult turtles and hatchlings, interfering with nesting behaviour and seaward migration. Hatchlings use natural light horizons over the ocean to locate the water; artificial lights can draw them inland, increasing mortality from exhaustion, dehydration, predation and traffic strike.

Nocturnally active seabirds and migratory shorebirds are vulnerable to disorientation, attraction and collision around artificial lights. Light pollution can disrupt navigation, increase grounding events, elevate collision risk with infrastructure, and reduce breeding success by altering foraging behaviour and parental care.

Artificial light can alter ecological processes in nearshore and coastal waters, including predator–prey interactions, diel activity patterns and reproductive timing. The guidelines highlight emerging evidence that light at night affects fish behaviour and reproduction and may interfere with spawning cues in shallow‑water coral reef systems.

Many marine and coastal invertebrates rely on natural light cues to regulate daily and seasonal activity. Artificial light can disrupt circadian rhythms, attraction and dispersal, with flow‑on effects for higher‑order species that depend on invertebrates for food, including fish, seabirds and bats.

Light pollution often acts cumulatively, interacting with other stressors such as habitat fragmentation, climate change and coastal development. Linear and exposed coastal environments (such as beaches, dunes and headlands) are particularly sensitive, meaning even small increases in light can lead to disproportionately large ecological impacts.

These guidelines include provide practical advice to reduce the impacts of artificial light on species such as shorebirds, seabirds, turtles, bats and insects.

For coastal councils, the guidelines support better planning, design and management of lighting in public spaces, infrastructure and development approvals.

Key principles include avoiding unnecessary lighting, directing light only where needed, using the lowest effective brightness, and choosing wildlife‑sensitive spectra.

The guidelines encourage early consideration of light impacts, adaptive management, and collaboration with regulators and communities to balance safety, amenity and biodiversity protection.

Local governments influence lighting through a range of their routine decision processes: therefore lighting policy should be a cross council responsibility. For example, lighting is influenced through:

• strategic and statutory planning
• development assessment
• design and management of public assets
• infrastructure upgrades
• event approvals
• community education and place management.

Coastal councils are well placed to play an important leadership role through demonstrating best practice on council-managed assets, setting clear expectations for private development, and supporting residents and businesses to reduce unnecessary night‑time lighting.

Light pollution disrupts the ability to see the stars clearly, and there is growing awareness of its impacts on Indigenous cultures.

For many Indigenous cultures around the world, stars are central to knowledge systems, traditions, and ways of life. The ability to observe and interpret stellar positions and movements is essential not only for daily activities such as navigation and seasonal planning, but also for the maintenance of cultural knowledge and intergenerational continuity.

An Australian study argues for the incorporation of Indigenous philosophies into light‑pollution management, highlighting how excessive artificial lighting threatens cultural practices grounded in night‑sky observation. They advocate for a transdisciplinary approach that respects and integrates Aboriginal and Torres Strait Islander perspectives into land‑use planning and lighting policy (Hamacher et al., 2020).