Light Pollution and Seabird Groundings: Understanding the Connection

Artificial Light at Night (ALAN) has become one of the fastest-growing forms of environmental pollution. From highways to coastal resorts, artificial lighting alters the natural lightscape that nocturnal wildlife depends on for navigation and behavior.

Decades of ecological research have shown that light pollution disrupts circadian rhythms, reproductive cycles, and migratory patterns across a wide range of species.

• Insects are drawn to blue and ultraviolet wavelengths, depleting local populations and affecting pollination networks.
• Sea turtles are disoriented by bright coastal lighting, leading hatchlings away from the ocean.
• Birds, particularly nocturnal and migratory species, are attracted to artificial lights, causing collisions, exhaustion, or “fallout” events during their breeding and fledging seasons.

As urban areas expand along coastlines, balancing human lighting needs with wildlife conservation has become an urgent challenge.

Ecological light pollution along the seashore poses risks to wildlife

Among these species, seabirds face a particularly serious yet less visible threat. Many navigate using starlight or moonlight reflections over the ocean. When artificial lights dominate the night sky, young seabirds can become disoriented, circling brightly lit areas until they fall to the ground—an event known as a “grounding.”

These incidents are particularly common in Hawai‘i, where dense coastal development overlaps with nesting colonies of the Wedge-tailed Shearwater (Ardenna pacifica), a seabird that raises its chicks near urban shorelines.

Scientific Investigation with MK350S Premium: Linking Light Spectrum to Seabird Groundings

To investigate this issue, researchers from the Hawai‘i Pacific University Marine Science Program at the Oceanic Institute conducted a multi-year study linking seabird groundings with artificial light characteristics on O‘ahu Island.

The team used the UPRtek MK350S Premium handheld spectrometer to analyze streetlight spectra along the southeastern coast—areas repeatedly identified as “fallout hotspots.” Their field measurements captured illuminance (lux), correlated color temperature (CCT), blue light ratio, and peak wavelength (λ).

Using MK350S Premium to measure ecological light pollution

Results revealed a clear trend: grounding sites were consistently associated with higher-CCT lighting, which emits greater proportions of short-wavelength (400–500 nm) blue light. In contrast, areas illuminated with warm, amber LEDs showed significantly fewer incidents.

This finding confirms that the spectral composition of light—not just brightness—plays a decisive role in wildlife disturbance. With the MK350S Premium, researchers could visualize the full spectral distribution on-site, providing quantitative evidence that guides lighting design for both safety and ecological protection.

Higher blue wavelengths lead to higher seabird grounding rates

Spectral Analysis Insights: From Research Data to Lighting Solutions

The spectral data obtained with the MK350S Premium offered a scientific foundation for future lighting guidelines in coastal Hawai‘i. By correlating groundings with spectral characteristics, the study demonstrated that reducing blue light emissions and lowering CCT values can effectively mitigate seabird fallout.

The MK350S Premium’s real-time spectral visualization and G-index analysis empowered field researchers to quickly identify problematic light sources and recommend targeted mitigation actions, such as switching to amber LEDs or adjusting fixture shielding and intensity levels.

These insights have already informed pilot lighting retrofits in coastal areas, balancing human safety, energy efficiency, and ecological sustainability.

Sustainable ecological lighting is crucial for our planet

Toward Sustainable Lighting for Humans and Wildlife

This collaborative research highlights how scientific lighting measurement tools can bridge the gap between technology and conservation. By applying precise spectral data to real-world ecological challenges, researchers and lighting designers can work together to protect vulnerable species without compromising human needs.

At UPRtek, we believe that understanding light—its color, composition, and ecological footprint—is the first step toward a more responsible world.
Together, let’s find your true colors, while protecting the planet’s natural ecosystems.

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