Written by FWC Sunday, 19 July 2009 06:01
FWC Featured Creature: Sea Turtles
Helping Florida’s sea turtles survive requires beach responsibility; Leave only footprints and keep beaches dark
Ancient creatures of the sea fight a battle each year to reproduce and survive in a world not always hospitable to them. Sea turtles nesting on Florida’s beaches face an uncertain future, according to the Florida Fish and Wildlife Conservation Commission’s (FWC) scientists. Threats come from encroachment on nesting beaches by coastal development and encounters with pollutants, beach debris and fishing gear.
A leatherback sea turtle digs a nest on a Florida beach while a young boy practices responsible beach behavior by not disturbing the female’s nesting patterns. The leatherback is the largest living turtle, reaching a weight of 2,000 pounds in some cases. (FWC photo)
Five species of sea turtles nest on Florida beaches, with the loggerhead showing up in the largest numbers. Green and leatherback sea turtles also nest in the Sunshine State. Two other species, Kemp’s Ridley and hawksbill sea turtles nest infrequently in Florida but inhabit Florida waters. The FWC lists the loggerhead as a threatened species with the other four listed as endangered.
However, the loggerhead’s status could change because of data collected showing a downward trend since 1998. During the 2007 April to September nesting season, scientists found the lowest number of loggerhead nests in 19 years. At the same time, the number of loggerheads found dead, sick or injured each year in Florida has more than doubled during the past decade. “If we don’t do something to reverse this trend, the loggerhead will also become endangered,” said Robbin Trindell, an FWC Imperiled Species Program administrator.
A loggerhead sea turtle hatchling heads to the ocean after hatching out of its nest. The loggerhead is the most common of Florida’s sea turtles. By the time this hatchling reaches the adult state, it will have increased its weightmore than 6,000 times. (FWC photo)
Nearly 90 percent of the loggerhead population that nests in the southeastern United States, nests on Florida’s beaches. This population is one of only two large loggerhead nesting populations worldwide. Sea turtles are air-breathing reptiles well-suited for sea life with a hydrodynamic-shaped shell, large and powerful front flippers. These physical characteristics enable them to dive deep into the ocean and to swim long distances.
Female loggerhead turtles begin coming on shore in the spring with peak months for laying eggs in June and July. The nesting female digs a hole with her hind flippers and then lays approximately 115 eggs. After covering the nest with sand, the massive creature, weighing nearly 300 pounds, makes her way back to the ocean. A female might come ashore two to five times during the nesting season. Amazingly, the females come back to the same beach where they hatched decades earlier. The males, once they make the long crawl after hatching out of the egg, never return to land.
Major disturbances to sea turtle nesting habits come from seawalls and beach nourishment projects. Individuals can help by following safe beach lighting suggestions, filling holes dug for sand castles and picking up litter. “Just one light can kill thousands of turtles over several years,” Trindell said. “Many lights burn all night, without contributing to human safety.”
Late in the summer, after an incubation of 55-70 days, the hatchlings begin breaking out of their shells and crawling out of the nest. Instinct tells the 1- to 2-inch hatchling to head toward the brightest horizon and away from dark silhouettes. In days long gone in Florida, the brightest horizon shone over the ocean, and the hatchlings would move away from the shadows on the dunes and begin the crawl to the sea. Nest predators might include raccoons, ghost crabs and fire ants.
In modern-day Florida, hatchlings must crawl through a battlefi eld of debris left by humans. Furniture discarded by beachgoers can obstruct a nesting female turtle or become a trap for the hatchlings. Avoiding firework leftovers strewn along the hatchling’s path can cause exhaustion and delay in getting to the water. If stranded on the beach when the sun rises, the hatchling’s chance for survival diminishes and dehydration and sun exposure become hazards.
“We can all help sea turtles survive,” Trindell said. “If we just take personal responsibility, we can go a long way to ensure the sea turtle co-exists with us for many more years to come.”
Buy a plate or decal and help sea turtles lay on the beach
The sea turtle hatchling displayed on the Florida specialty license plate does more than just adorn the bumper of a car. The purchase of the specialty tag goes a long way to help protect this living fossil from extinction. The fees collected go directly into sea turtle research and conservation. The loggerhead hatchling represents hope for a safe passage from the nest to the water, a dangerous endeavor for a 1- to 2-inch creature.
Purchasing a specialty tag helps fund the Sea Turtle Grants Program, which distributes funds each year to support sea turtle research, conservation and education programs. Approximately 30 percent is distributed to the grants program, which is administered by the non-profit Caribbean Conservation Corporation. The other 70 percent of the funding generated by sales of the tag goes to the FWC’s Marine Turtle Protection Program to support research and management activities related to sea turtles.
Since 1992, the sea turtle also has been featured on boat registration decals that have helped fund research and conservation efforts. These decals can be purchased for $5 each, as a voluntary add-on to boat registration fees or from the FWC’s Web site, MyFWC.com . The newest decal features a Kemp’s Ridley turtle by FWC artist Liz West.
Sea turtle license plates may be purchased at any authorized motor vehicle office, such as Florida’s Department of Highway Safety and Motor Vehicles, local tax collector’s office or a licensed tag agent or go to buyaplate.com . Decals may be purchased at www.floridaconservation.org/seaturtle/Decals/Turtle_Decals.htm .
Dedicated to learning more about ancient creatures of the sea
Blair Witherington keeps a close watch on sea turtles. Witherington returned from Oman, a country in the Middle East, in April excited about the future of loggerhead turtles, despite discouraging news in Florida from nesting counts in 2007.
Witherington, a research scientist with the FWC’s Fish and Wildlife Research Institute (FWRI), studies sea turtles daily. “The loggerhead population is in serious decline,” Witherington said. “Eighty percent of the world’s loggerheads nest on beaches in Florida and on the island of Masirah in the Indian Ocean off the coast of Oman.”
Blair Witherington holds a Kemp’s Ridley sea turtle, one of the rarest turtles in the world, as he and his team conduct research off the coast of Florida. (FWC photo)
In Florida, the loggerhead is the most common sea turtle. But worldwide, the loggerhead is rare, said Witherington, who went to Masirah to help set up a monitoring program for the threatened reptile, similar to what Florida uses on its 33 index nesting beaches.
Witherington coordinates Florida’s Index Nesting Beach Survey, which is conducted annually from May 15 to Aug. 31. The process involves volunteers who go out before sunrise each morning, seven days a week during the nesting season. Volunteers monitor nests laid during the night and report false crawls – signs of a sea turtle’s flippers in the sand but no nest. “There are indications that there may be declining numbers in the loggerhead population in Masirah as well,” Witherington said. “But we need reliable data to determine it conclusively.”
Witherington received his Ph.D. from the University of Florida, and his dissertation addressed the orientation of hatchling sea turtles and the effect of light on their journey to the sea. “If they head in the wrong direction, they die,” Witherington said of the effect of direct lighting on the beach.
Counties and municipalities in the majority of the sea turtle nesting areas in Florida now have ordinances in place for lighting management, something that brings a smile to Witherington’s face. “This is absolutely a success story in Florida,” he said. “We have made headway in conservation efforts for sea turtles.”
Witherington also conducts neo-natal research. For years, scientists have called the posthatchling’s first year, “the lost year” because no one knew where the hatchlings went once they made it to the ocean from the nesting beach. Witherington and his team discovered that hatchling loggerheads and green turtles migrate out to the floating, open-ocean sargassum (seaweed) community offshore from nesting beaches.
They also found hawksbill and Kemp’s Ridley sea turtles that are approximately a year old. “It’s very exciting to find small Kemp’s Ridley because they are the rarest of sea turtles,” he said. “We usually see large juveniles or adults swimming in Florida’s waters.”
While concerns remain about the loggerhead’s survival, Witherington believes the work done by the FWC and other groups, such as the U.S. Fish and Wildlife Service and the National Marine Fisheries Service, will help conserve this giant reptile. “I work with a team of skilled and well-informed people,” he said. And the team extends beyond the FWC with more than 2,000 people in the state doing nesting counts and conveying conservation messages. “Florida would be much poorer without our sea turtles,” Witherington said.
To learn more about sea turtles, visit FWC’s Web site at MyFWC.com/seaturtle .
— A PRODUCT OF THE FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION’S COMMUNITY OUTREACH —
This article originally published on July 19, 2009.
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