Reducing Light Pollution: Saving Sea Turtles

Reducing light pollution is crucial for the survival of sea turtles, as artificial light disrupts their reproduction and nesting behaviour. Sea turtles prefer to nest on naturally dark beaches, but coastal development has led to an increase in artificial lighting from sources such as streetlights, hotels, and residences. This lighting discourages female turtles from coming ashore to nest and can cause disorientation in hatchlings, leading them away from the ocean and towards potential dangers such as predators and dehydration. To protect sea turtles, it is essential to reduce light pollution during nesting and hatching seasons by turning off unnecessary lights, using low-intensity amber or red lighting, and shielding lights from view of the beach.

Use low-pressure sodium-vapor lighting (LPS) instead of normal lights

Light pollution is a significant threat to sea turtles' reproduction and survival. Artificial light discourages female turtles from nesting on beaches, and can cause hatchlings to become disoriented and wander away from the ocean, making them more vulnerable to predators, dehydration, and vehicle strikes.

To address this issue, it is recommended to use low-pressure sodium-vapor lighting (LPS) instead of normal lights. LPS lights are monochromatic yellow in color and have the longest wavelengths, which sea turtles do not detect as easily. Here are some specific ways to implement LPS lighting to reduce the impact on sea turtles:

• Lower mounting height: Mount lighting fixtures as low to the ground as possible to minimize their visibility from the beach. This also ensures that the light illuminates only the intended area, improving functionality and energy efficiency.
• Shielding: Use fixtures that direct light downward and away from the beach, shielding the light source from direct view. This can be achieved through simple screens, such as aluminum flashing, or by planting vegetation like ornamental hedges.
• Long wavelengths: Sea turtles are less disturbed by long-wavelength light (560-580 nanometers or longer), which appears amber, orange, or red. Using these wavelengths can help reduce disorientation and protect sea turtle populations.
• Alternative sources: If lighting is necessary, LPS is often the best choice as it is the least detrimental to sea turtles. However, other alternatives such as Turtle Safe Lighting, which emits narrow portions of the visible light spectrum in red, can also be considered.
• Lower intensity: Reduce light intensity to the minimum required for the intended purpose. Lower intensity lighting can still provide adequate illumination while minimizing the impact on sea turtles.

By implementing these measures, coastal communities can significantly reduce the negative impact of artificial lighting on sea turtles, helping to protect their reproduction and survival.

Turn off unnecessary lights

Turning off unnecessary lights is one of the most effective ways to reduce light pollution and help protect sea turtles. This is especially important during the nesting and hatching seasons, typically from 7 pm to midnight.

Turn off lights visible from the beach:

• Conduct a lighting inspection to identify lights that are visible from the beach, including direct lighting (lights visible from the beach) and indirect lighting (illuminated buildings or landscaping visible from the beach).
• Turn off or replace lights that are visible from the beach with sea-turtle-friendly alternatives, such as low-pressure sodium-vapor lighting (LPS) or turtle-safe red lights.
• If turning off lights is not possible, consider using motion-sensitive lights, which only turn on when necessary and reduce the duration of illumination.

Reduce sky-glow:

• Sky-glow is the cumulative effect of lights from an area, including lights inside and outside buildings, street lights, and recreational facilities, which can affect sea turtles.
• To reduce sky-glow, ensure that all outdoor lighting is directed downwards and shielded to minimise light spill.
• Use low-intensity amber or red lighting, as these colours have a weaker effect on turtles.
• Avoid using blue, green, UV, and white lights, as these have the most harmful effects on turtles.

By implementing these measures, we can significantly reduce light pollution and help protect sea turtle reproduction and survival.

Shield the light source

Shielding light sources is an important way to reduce light pollution and help sea turtles. Here are some ways to shield light sources to protect these magnificent creatures:

Shielding Fixtures and Bulbs

One of the most effective ways to shield light is to use fixtures that are designed to be turtle-friendly. These fixtures have specific characteristics that minimise light trespass and ensure that the light source is not visible from the beach. This involves using shields, covers, or baffles to block the light from shining towards the beach or adjacent waterlines. The type of shield depends on the fixture and its location. For example, balcony lights can be shielded to restrict light to the balcony itself, while pole lights in parking lots can be shielded and angled away from the beach.

Beachside Shielding

Beachside shielding is crucial to prevent light from shining onto the beach or nearby water. This can be achieved by using specific fixtures or by modifying existing ones. For instance, adding a metal or dark plastic cover to an existing fixture can block light trespass, but it's important to ensure that the light source cannot be seen from any vantage point on the beach.

Vegetation Buffers

Planting or improving vegetation buffers, such as sea grapes and other native beach vegetation, between the light source and the beach can help block light from reaching the beach. This natural approach not only reduces light pollution but also provides additional benefits to the ecosystem.

Window Treatments and Tinting

Interior lights can also disorient sea turtles, so it's important to shield them as well. Window treatments such as blinds, curtains, or opaque coverings can be used to block light from escaping through windows. Additionally, applying window tint that meets specific transmittance requirements can effectively reduce the amount of light that reaches the beach, minimising the impact on sea turtles.

Lighting Direction and Height

The direction and height of lighting fixtures play a crucial role in shielding. Lights should be mounted as low as possible, and the bulbs should produce the lowest wattage/lumens necessary. Fixtures should be angled downward and away from the beach to ensure that light does not spill onto the nesting areas.

By implementing these shielding methods, we can significantly reduce the impact of artificial lighting on sea turtles, helping to protect their reproduction, nesting, and overall survival.

Use long-wavelength lights

To protect sea turtles, it is important to reduce light pollution, especially near their nesting beaches. Artificial light is a high-risk threat to sea turtles' reproduction and survival.

Sea turtles are less disturbed by long-wavelength lights (560 nanometers or longer). These lights appear amber, orange, or red and do not contain shorter spectrums of light. Long-wavelength lights are also known as "Turtle Safe Lighting".

The Florida Fish and Wildlife Conservation Commission (FWC) has established three golden rules for beachfront lighting to reduce the impact of artificial lighting on sea turtles:

• Fixtures must be mounted as low as possible while still serving their intended purpose.
• Bulbs must produce the lowest wattage/lumens necessary for their intended purpose.
• Bulbs must produce only long-wavelength light (560 nm or greater, which appears amber, orange, or red).

To comply with these rules, property owners can take several measures:

• Use low-wattage amber, orange, or red LED bulbs.
• Ensure fixtures are shielded to direct light downward and away from the beach.
• Avoid flood, spot, and pole lighting, which can illuminate large areas and disorient sea turtles.
• Plant vegetation buffers, such as sea grapes and other native beach plants, to block light from reaching the beach.
• Use motion-activated lights with short time settings to minimize the duration of illumination.
• Apply window tint or treatments (blinds, curtains) to prevent interior lights from being visible from the beach.

By following these guidelines, property owners can help reduce the impact of artificial lighting on sea turtles, contributing to their protection and conservation.

Remove or reposition unnecessary fixtures

Light pollution is a significant threat to sea turtles, affecting their reproduction and survival. To help sea turtles, it is important to reduce artificial lighting near their nesting beaches.

One way to achieve this is by removing or repositioning unnecessary fixtures. Here are some detailed instructions to reduce light pollution by addressing light fixtures:

• Identify unnecessary lights, such as decorative lighting like runner lights or uplighting of vegetation, and turn them off or remove them.
• Reposition fixtures that are visible from the beach. Move them away from windows or balconies to minimise their impact on sea turtles.
• Replace fixtures with excessive lumens with low-wattage bulbs.
• Replace fixtures that scatter light with directional or recessed fixtures that point down and away from the beach.
• If fixtures cannot be modified, consider disabling or removing them entirely.
• For lights that are necessary for safety, consider adding shields to direct the light downward and away from the beach, ensuring the bulb has a long wavelength.
• Turn off balcony lights that are not shielded and restrict light to the balcony with long-wavelength bulbs.
• For utility pole lights, request that the power company turns them off or add additional shielding to minimise the direct light source.
• Replace pole lights in parking lots with full cut-off fixtures angled away from the beach, covered by shields, and fitted with long-wavelength light sources.
• Pool lights should be set to an amber or red colour during the marine turtle nesting season to reduce the cumulative glow.
• Turn off all decorative lights, such as uplights, string lights, or lights in trees, during the sea turtle nesting season.
• For interior lights, close window coverings at night, use fixtures with shades, and move lamps away from windows to minimise their impact on sea turtles.

Frequently asked questions