Reducing the Impact of Artificial Light on Sea Turtles

Keep beachfront lighting turned off | Reduce the number of lights near nesting beaches | Reduce light reaching the nesting beach | Place security lighting on motion-sensitive switches | Apply dark window tinting to windows | Reduce light visible from beach | Replace existing light fixtures | Summary

The following are a few techniques designed to reduce the effects of artificial lighting on sea turtles:

• Keep beachfront lighting turned off.
• Reduce the number of lights near nesting beaches.
• Reduce light reaching the nesting beach.
• Place security lighting on motion-sensitive switches.
• Apply dark window tinting to windows.
• Reduce light visible from beach and
• Replace existing light fixtures.

Keep beachfront lighting turned off

Keep beachfront lighting turned off during the nesting and hatching season described in the table below.

Reduce the number of lights near nesting beaches

Reduce the number of lights near nesting beaches to the minimum necessary to accomplish the lighting goal. Lighting used for purely decorative purposes should be kept off.

Reduce light reaching the nesting beach

Reduce light reaching the nesting beach by lowering, shielding, recessing and/or redirecting light sources. Any light source visible to an observer on the beach is likely to affect sea turtles. Light sources that are indirectly visible from the beach, such as those that shine against buildings or vegetation seen from the beach, also cause problems for sea turtles. For this reason, low-mounted down lights are preferred over lighting that shines upward.

Place security lighting on motion-sensitive switches

Place security lighting on motion-sensitive switches that keep lighting off when it is not needed. Lights that come on only when approached can be quite effective for security purposes.

Apply dark window tinting to windows

Apply dark window tinting to windows visible from the beach and draw curtains after dark.

Reduce light visible from beach

Many lighting applications are known to affect sea turtles, including:

• porch
• pool
• street
• stairway
• walkway
• parking lot
• security and interior lighting
• floodlights
• up-lights
• spotlights
• area lighting
• lighted commercial signs
• flashlights
• kerosene lanterns
• open fires
• car headlights and
• "bug-zappers" (which emit light that both insects and sea turtles see).

The best way for beachfront residents or visitors to determine whether their lighting could adversely affect sea turtles is to visit the adjacent beach at night, a few hundred feet either way, and look for light. Light visible either directly or indirectly from any portion of the beach should be reduced by employing the methods in Reduce light reaching the nesting beach.

Replace existing light fixtures

Replace existing light fixtures with those that emit light less detrimental to sea turtles. Studies have shown that light in certain wavelengths does not affect hatchling and nesting sea turtles as much as others. For instance, a pure yellow light, such as that from a low-pressure sodium vapor source, does not appear as attractive to turtles as some other lights. Yellow incandescent light bulbs also are preferred if they are kept at low wattage. Examples of lighting inappropriate near sea turtle nesting beaches include

• fluorescent
• mercury vapor
• high pressure sodium vapor
• metal halide and
• white incandescent lighting.

Summary

Florida's beaches serve an important nesting habitat for several species of threatened and endangered sea turtles. Artificial light on or near nesting beaches can negatively affect the nesting process by interfering with normal nocturnal behaviors of sea turtles.