SCCF marks first island nest as sea turtle season begins
UPDATE: On May 2, SCCF volunteer Rachel Walsh found the first loggerhead nest of the season for Captiva. On May 3, SCCF volunteer Nancy Riley found a second loggerhead on Captiva. Also on May 3, SCCF volunteers Diane Clark and Irene Nolan marked off the first loggerhead nest on the west end of Sanibel. The turtle was affectionately dubbed “Cookie Dough” when she previously nested on the islands in 2017 and 2019. According to the data available as of today, two additional loggerhead nests have been found on Sanibel’s west end.
Sea turtle nesting season has officially kicked off on the islands with the first nest on the books.
On the morning of April 27, the Sanibel-Captiva Conservation Foundation’s Sea Turtle Team recorded the first nest for the 2021 season — a loggerhead nest — on the east end of Sanibel. Officials also reported that two false crawls — where sea turtle tracks are identified, without a nest — on the same day.
“Last year, our first nest of the season was on April 15,” SCCF Director of Coastal Wildlife Kelly Sloan reported, adding that the turtle team surveys several miles between Sanibel and Captiva.
April 15 is the official start date in Florida for nesting season, which will run through October.
This year’s first nest along the Gulf Coast — a loggerhead — was found on April 21 on Manasota Key. It was found by Coastal Wildlife Club personnel at Charlotte County’s Stump Pass Beach State Park.
Sea turtle monitoring originally began on Sanibel in the 1950s with Charles LeBuff and Caretta Research Inc., making it one of the longest-running monitoring programs in the country. When Caretta Research disbanded in 1992, the SCCF took over the program and continues to manage it today.
Loggerhead is the most common marine turtle species to nest on the islands, followed by the green sea turtle. Leatherbacks and Kemp’s ridleys are rarer, but the species have nested on the islands before.
“Loggerheads are by far the most common,” Sloan said.
Loggerheads typically grow 3 feet to 3 1/2 feet long and weigh 150 to 300 pounds. With large, bulky block-like heads and powerful jaws — how they got their name — they prey on hard-shelled mollusks, conches and such. Females lay three to six nests per year on average but nest every two to three years.
Green sea turtles are bigger, about 3 1/2 feet to 4 feet and weighing upward of 350 or 400 pounds. Their head is small relative to their body, and they are named “green” because their fat is green-colored due to a mostly vegetarian diet of grasses and algae. Greens lay three to six nests every other year.
“They do have a stronger every-other-year (nesting) pattern,” Sloan said.
For Sanibel and Captiva, 34 green nests were recorded in 2017 and 32 nests in 2019.
“We’re expecting a big green season,” she said. “They’re on a two-year nesting cycle, so this would be another big year for them.”
Leatherbacks are the largest species, growing 6 feet to 7 feet in length and weighing 500 to 1,500 pounds. With a diet consisting almost entirely of jellyfish, they do not have a typical “hard shell” like the others; theirs is a “leathery” shell with seven distinct ridges along it, which is unique to them.
Nesting every couple of years, leatherback turtles typically lay five to eight nests.
“We don’t know much about leatherbacks nesting on the Gulf Coast,” Sloan said, explaining that the species is known to nest more frequently on Florida’s east coast. “But usually we get one a year.”
Last season, one leatherback — satellite tagged and named Juniper — laid multiple island nests.
The Kemp’s ridley turtle is the smallest species and nests differently than the rest.
They average about 1 1/2 feet to 2 feet and can weigh 50 to 100 pounds. Kemp’s ridleys are omnivorous so they will eat a range of different prey, but their diet is mostly comprised of crabs. Nesting every one to three years, they lay two to four nests — but during the day, not night.
“They’re main nesting site is in southern Texas and Mexico,” Sloan said.
As part of its Sea Turtle Program, the SCCF is responsible for monitoring roughly 18 miles of beach and nesting habitat that stretches from the Sanibel Lighthouse up to Redfish Pass on both islands.
“The monitoring program involves surveying the beach every morning at sunrise,” she said. “At this time of the year, we look for new crawls.”
“When we find a nest, we verify the egg chamber and put a screen on top because we have a coyote predation problem — or at least we did, but the screens are very effective,” Sloan added. “We put up stakes to keep people out and also to mark the nests.”
The turtle team checks the nests daily for predator intrusion, fire ants, tide washouts and such.
“When they hatch, we give them three days to emerge naturally and then we’ll go and see how many hatched and how many didn’t, so we know how successful the season was,” she said.
There are about 100 volunteers who participate in the program.
“They put in thousands and thousands of hours of work each year and we couldn’t do it without them,” Sloan said.
In addition to the nest monitoring, SCCF’s Sea Turtle Program has a research component.
“It’s a very important component because it helps us identify emerging threats to turtles, which helps us protect them better,” she said.
There is a night-time tagging program to mark and identify individual turtles in an effort learn more about their behavior and genetic connectively with other nearby islands and nesting areas. There is also a satellite tagging program for greens where ones were tagged in 2017, 2018 and 2019 to learn more.
“They didn’t nest on the west coast in big numbers until the last 10 to 20 years,” Sloan said.
Funded through the Florida RESTORE Act Centers of Excellence program, the SCCF also runs a red tide project in which blood samples are taken from females as they nest, plus their eggs are tested.
“We’re really interested in learning about the long-term or chronic impacts on the population,” she said.
To date, SCCF staff has only analyzed samples from 2019.
“We are seeing brevetoxin concentrations in both,” Sloan said of the results. “It seems the toxins are persistent in the environment, so somehow the animals are picking them up after the bloom dissipated.”
As for having a successful nesting season this year, there are ways that beach-goers can help.
“We absolutely need the public’s help to keep the beaches safe for nesting and hatching sea turtles,” she said. “We cannot do it without them.”
The SCCF provided the following tips to help keep the islands sea turtle-friendly:
– Turn off or shield all lights that are visible from the beach. Do not use flashlights or cell phone lights on the beach. If necessary, use amber or red LED bulbs.
– Remove all beach furniture and equipment from the beach at night by 9 p.m.
– Dispose of fishing line properly to avoid wildlife entanglement.
– Fill in holes that can trap hatchlings and nesting sea turtles.
– Do not disturb nesting turtles — please do not to get too close, shine lights on, or take flash photos of nesting sea turtles.
– Pick up litter because it attracts predators.
“And help spread the word because a lot of people are here on vacation and may not know,” Sloan said.
Boaters can also do their part to keep the surrounding waters sea turtle-friendly.
“Sea turtle are getting closer to shore right now as they’re preparing to nest,” she said. “Often it’s the same place as where boaters are.”
– Avoid the area along the beach, if possible.
– Have a designated spotter on the boat to look out for sea turtles.
– Wear polarized sunglasses to help with spotting sea turtles.
– Go as slow as possible in areas where sea turtles are or might be.
“Sea turtles don’t dive as fast as people think they do,” Sloan said.
For more ways to protect and care for sea turtles, visit https://sancaplifesavers.org/.
To report a nest or false crawl, or for concerns about nesting or injured sea turtles, contact the SCCF Sea Turtle Hotline at 978-728-3663 (978-SAVE-ONE). For more about SCCF, visit www.sccf.org.