By Nirvi Shah
More leatherback turtles have made their way onto Palm Beach County beaches this nesting season than in the last five years — to the cautious delight of sea turtle protectors.
Early totals show there were at least 457 leatherback nests along the beaches tracked by the county since the season began, said Carly DeMaye, who oversees sea turtle protection for the county. The previous record was 429 nests in 2007.
“We hope we will continue seeing an exponential increase in leatherback nesting,” DeMaye said. In 1996, the county recorded just 94 leatherback nests along its coast.
She said there is no one reason for the surge. Leatherbacks have been listed as an endangered species for nearly 40 years by the federal government, and the increase in nests could be the culmination of decades of conservation efforts. Or, a new nesting colony may have settled in the area, or more turtles could be making their way here because they find other regions less suitable for laying eggs.
But Florida International University Professor John Fletemeyer is more skeptical about whether the increase in sea turtle nests actually means an increase in the sea turtle population. He works at the university's Laboratory for Coastal Research in Fort Lauderdale and monitors about three miles of Palm Beach County’s coastline in Delray Beach.
“To be excited about a good year vs. a bad year is kind of overly optimistic,” Fletemeyer said. “In all animal populations, everything is cyclical.”
For example he said, the majority of loggerhead turtles nest every two years, and a large group nests every three.
“When you see a spike in loggerhead nesting, it’s more likely a convergence of the two- and three-year nesters every six years” than an actual increase in the turtle’s population, he said.
Earlier this summer, Fletemeyer said Delray was home to 14 leatherback nests this year so far, 70 loggerhead nests and two green sea turtle nests — increases over last year, although he could not say just how much of an increase. The county’s numbers include beaches in Boca Raton, Juno Beach, Jupiter, Ocean Ridge, Palm Beach and Singer Island. Final numbers that include the entire county coastline won’t be tallied until December.
Although sea turtle nesting season stretches from March to October, most leatherbacks would have already laid eggs by now, said Chris Johnson, a biologist at Loggerhead Marinelife Center in Juno Beach. They typically nest from late February through July.
Juno Beach alone has recorded 277 nests so far this year, he said, compared to a previous record of 158. He was more encouraged by the increase than Fletemeyer.
“We are excited and encouraged by the uptick in nesting numbers, but leatherbacks face many threats here on the nesting beach and in the open ocean,” Johnson said.
Although they are among the largest of the turtles that nest along Florida’s coastline and can easily grow to 2,000 pounds, their size doesn’t make them particularly hardy, DeMaye said. The species has been devasted by commercial fishing and leatherbacks continue to be affected by longline fishing.
Leatherbacks don't have a hard shell the way most sea turtles do, she said, because they are designed to dive deeply for food. Their shell of small rubbery plates allows them to dive deep without being affected by the water pressure.
While the leatherbacks appear to be increasing their presence in the Atlantic Ocean, Johnson said in the Pacific, the numbers have declined dramatically and he blames commercial fisheries for their decline in that ocean.
Along with leatherbacks, loggerheads and green sea turtle nests in Palm Beach County, hawksbill and rare Kemp’s ridley turtles are found offshore. All but loggerheads are endangered species, although there are petitions to push loggerheads from the threatened to endangered designation, said David Anderson, a marine turtle specialist at Gumbo Limbo Nature Center in Boca Raton. Their status is under review by the U.S. Fish & Wildlife Service, which labeled them threatened in 1978. Reclassifying the reptile seems especially important now, he said, because loggerheads aren’t having a good nesting season.
Loggerheads will continue to nest through August, but their numbers so far are on pace with a record low season set in 2007.
Gumbo Limbo, which monitors about five miles of beach at the southern end of the county, typically counts about 500 loggerhead nests each season. So far, they have recorded fewer than 360 so far, which puts them off track to meet last years’ total.
“As each day passes it’s going to be tough to catch up,” Anderson said.
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