A high-pressure sodium bulb was swapped for an LED bulb, and the fixtures were switched to shielded fixtures.
New lights lining coastal roadways could make all the difference for sea turtle disorientations.
A combined effort between Florida Power and Light, the Florida Fish and Wildlife Conservation Commission and Florida Department of Transportation could make that happen.
The three entities came together Aug. 24 and Aug. 25 to test new lights and fixtures in Bradenton Beach in the 500-1200 blocks of Gulf Drive South.
“If this light shows with all these entities to be turtle friendly, it could be the saving grace with everything we’re having so much trouble with,” said Suzi Fox, executive director of the Anna Maria Island Turtle Watch and Shorebird Monitoring.
Bradenton Beach Mayor Bill Shearon said he worked with Fox and Longboat Key Vice Mayor Jack Duncan to pursue the test. Shearon offered to be the “test site” three months ago, he said.
Fox said a similar test would be held on Turtle Beach in Sarasota. The locations were chosen because they both have streetlights on coastal roads that are managed by the DOT and nothing obstructs the lights’ path to the beach.
For each test, a high-pressure sodium bulb was swapped for an LED bulb, and the fixtures were switched to shielded fixtures.
Fox, last week, said a crew from the three entities would wait overnight by soon-to-hatch nests. For each test run, 30 hatchlings would be used to measure the light’s effect on their speed and direction.
Eleven streetlights along Gulf Drive, perpendicular to the test site, were shut off to avoid interference with the new fixtures. Of the eight blocks in the test, four were fitted with new lights, and four were left dark to maintain the control site.
“If we don’t have a nest hatch out, we won’t have a test,” Fox said before the test run.
Fox said LED lights emit red wavelengths, which are not perceptible to sea turtles. Turtle-friendly lights are often amber, which is 90 percent invisible to sea turtles, but LED lights can’t be seen at all, said Fox.
A similar test was run 10 years ago, and did not produce desirable effects. However, Fox remained hopeful this collaboration would produce a new turtle friendly light for streetlights.
“It’s just a test. The first step is getting one that’s certified,” said Fox.
In order to install any new streetlights, they must be certified as turtle friendly by the FWC and approved by the DOT and FPL.
While most beachside buildings are in compliance with the island cities’ light ordinances during sea turtle nesting season — May through October — Fox said there is a continuous problem with streetlights and sky glow.
The problem has been particularly pronounced this season, with more than double the number of hatchling disorientations. Fox said following beach renourishment, which completed in March, a higher number of disorientations should be expected, but this season’s numbers are troubling.
Sea turtles use the reflection of the moon and the stars on the water to guide them to the Gulf. Visible lights coming from the opposite direction can misguide the hatchlings, which have limited energy, numerous predators and can easily die from dehydration if distracted.
“This is a very important test and this has to be just right. There are no (turtle friendly) approved streetlights in the state of Florida,” said Shearon before the test. “Shields alone are by no means an answer.”
Test results — if any — were not available by Islander press time.