Sea turtle nesting season off to a big start
Sea turtle nesting season kicked off last week on the islands with the first two nests of the year recorded on Sanibel – a loggerhead on the very first day, followed by a rare leatherback.
April 15 officially marked the first day of season, which runs through October.
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 Sanibel-Captiva Conservation Foundation took up the program.
“Currently, we are at two nests on Sanibel,” Jack Brzoza, sea turtle biologist with SCCF’s Coastal Wildlife Program and Sea Turtle Program, said on April 17. “But, no nests on Captiva yet.”
On April 15, staff found the first one of the season – a loggerhead nest on the east end of Sanibel. According to officials, it is the earliest one ever documented for the islands based on records. Two days later, staff located a second nest from a leatherback turtle on the west end-central area of Sanibel.
“Which is pretty rare and super exciting for the Gulf coast and, particularly, Sanibel,” he said.
Prior to the official start of season, the SCCF documented a couple of false crawls. On April 1, a leatherback was reported on Sanibel, and a loggerhead was reported on April 14 on Captiva.
“That was the first sea turtle activity that we documented,” Brzoza said.
Loggerheads are the most common marine turtle species to nest on the islands, followed by green sea turtles, which are still unusual. Leatherbacks and Kemp’s ridleys are rarer but have nested before.
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 only nest every couple years.
“It’s the most common sea turtle that nests in the whole state of Florida,” he said.
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.
“Green sea turtles are much more common nesters on the east coast of Florida,” Brzoza said. “But in recent years, we are kind of seeing a rise in their nesting activity (on the islands).
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.
“They’re a lot more common on the east coast of Florida,” he said, adding that the one nest already recorded this year is rare. “It’s intermittent, and it’s not as consistent as it is on the east coast.”
The Kemp’s ridley turtle is the smallest species.
“They’re also critically endangered, so they’re pretty rare,” Brzoza said.
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 other year or more, they normally lay two to four nests – but not at night-time.
“They are day-time nesters. Every other species comes ashore at night,” he said, noting that their nesting sites are almost solely in Mexico and Texas. “The adults typically don’t nest here.”
“Another thing that is unique is they will also nest in large groups,” Brzoza added.
As part of its Sea Turtle Program, the SCCF is responsible for monitoring the roughly 18 miles of beach that stretch from the Sanibel Lighthouse up to Redfish Pass and it covers both islands.
“We’re looking for signs of new turtle activity,” he said, explaining that nests are documented and roped off, then monitored after. “Our program has over 100 volunteers and they do a lot for us.”
Unfortunately, due to the COVID-19 pandemic and state and local “stay at home” orders, SCCF program coordinators have had to make adjustments to the operation to keep everyone safe.
“Currently, given the conditions, we’re operating on a staff-only basis,” Brzoza said. “So only staff is doing the monitoring activity right now. We’re not utilizing our volunteers.”
According to officials, staff from the Marine Lab, Sanibel Sea School and Native Landscapes & Garden Center are stepping up to take solo shifts monitoring the beaches; lab staff are also helping with lab tests associated with bloodwork. Wildlife & Habitat Management staff are helping as needed.
When monitoring, they are practicing social distancing, wearing gloves and disinfecting.
“We’re definitely being a lot more careful, and we’re trying to be as safe as we can be,” he said.
“Things may not be the same as far as logistics or structural details, but nothing has really changed for the turtles,” Brzoza added. “We’re adapting and doing everything we can, so we are monitoring to the best of our abilities.”
As people continue to visit or walk the beach as a form of recreation during these unprecedented times, the SCCF provided the following tips and suggestions 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.
– Dispose of fishing line properly to avoid wildlife entanglement.
– Fill in large 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.
“Help keep the beaches clean and suitable for nesting habitat,” he said.
For recreational boaters, take note that reproductive-age turtles are close to shore.
“Really keep an eye out when you’re out on your boat,” Brzoza said. “Slow down and pay attention to those idle zones.”
To report a nest or false crawl, or for concerns about nesting or injured turtles, contact the SCCF Sea Turtle Hotline at 978-728-3663 (978-SAVE-ONE). For more on the program, visit www.sccf.org.