By Mary Lundeberg – Although they’re making a comeback, green sea turtles and loggerhead turtles remain threatened. A record number have nested in Florida this season and that’s good news in spite of ongoing threats. Brenda Bossman, who oversees Don Pedro Island Turtle Patrol, reports 164 green nests and 521 loggerhead nests as of October 1. That’s a big increase from 26 greens reported in 2015.
Florida has more than 90 percent of sea turtle nests in the U.S. That includes greens, loggerheads, Kemp’s Ridley, and Leatherbacks (the latter nest only on the east coast). When ready to breed, the female green sea turtle will swim hundreds of miles from her foraging area to the waters off her nesting beach. How she navigates entire ocean basins to return to the same area where she hatched remains a mystery.
After mating with one or more males, the sea turtle will nest several times from May through September. She typically lays an average of four clutches with about 135 eggs per nest. Her two-hour nesting process involves crawling onshore, digging a large pit to create a chamber for her eggs, and then covering them. She ends up moving about a ton of beach sand.
Green sea turtle hatchlings weigh half a pound and measure 2 inches in length. They can grow up to four feet long, weigh as much as 350 pounds, and live 70 years. Living so long is a longshot when you consider less than 1 in 1,000 hatchlings reaches sexual maturity in 25 years.
After about 50-60 days of incubation, hatchlings emerge at night, facing numerous predators, including armadillos, seabirds, crabs, raccoons, sharks, insects like red ants, and humans. Hatchlings use the brightness of the open sky above the water to navigate seaward. Artificial lights lead hatchlings astray and expose them to predators. Thousands of hatchlings die each year because of light pollution.
Another threat to sea turtles is getting caught in fishing gear also known as bycatch. Other threats include loss of nesting habitat due to human development. Some nests are flooded because of storms and rising sea levels. Higher temperatures of the sand can produce more females than males. Excessive heat can kill the baby turtles before they hatch.
When encountering a nesting turtle, please observe from a distance, and turn off lights and flashlights on the beach during nesting season. Researchers note that almost 100 percent of stranded hatchlings ingested plastic, so please keep balloons and trash off the beach. Green turtles represent a conservation success story, but they remain vulnerable. A big thank you to all of the dedicated volunteers and groups that monitor turtle nests locally and in other areas of Florida.
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