Sea Turtle Nesting Activity Subsides As Fall Arrives At The Florida-Georgia Border

As the calendar turns to September, it’s a surprise to find a new sea turtle nest. Instead, mostly happening this time of year is the emergence of hatchlings.

Amelia Island, FL and Cumberland Island, GA

Flanking the St. Marys River at the Florida-Georgia border are two Southern barrier islands on the Atlantic coast. In the Sunshine State is Florida’s most northeastern island, Amelia. On the other side of the river is the wild isle, Cumberland, Georgia’s most southeastern barrier island.

The heaviest sea turtle nesting happens during June and July each year. Then in August and September it becomes largely the hatchling phase of season, when those previously established nests emerge. As of mid-September, approximately 80% of the nests have hatched on both islands and nest inventories recorded.

How Long Is Sea Turtle Nesting Season?

The annual sea turtle nesting season is from May 1 through Oct. 31st. But as the calendar turns to September, it’s more of a surprise to find a new nest. Sea turtle species are listed as either “threatened” or “endangered” under the Endangered Species Act.

The majority of sea turtle nests, by far, around the Florida-Georgia border and elsewhere in these two Southern states are loggerheads (Caretta caretta). During annual sea turtle nesting season, females that have reached reproduction age land on beaches. They arrive at night to dig nests and deposit eggs.

Sea Turtle Nesting Counts 2021

Cumberland Island’s beaches attract the highest amount of sea turtle nesting each year in the state of Georgia (“25 to 30 percent of statewide nesting total”), according to the park service. Cumberland Island National Seashore reported a total of 645 sea turtle nests in 2021 (data through mid-September).

On the other side of the river, Amelia Island typically records hundreds less nests each year, than Cumberland Island. This season’s count on Amelia Island was 241 sea turtle nests as of mid-September, 2021. Approximately 190 of the nests were located within the segment of the beachfront identified as the “AISTW beach” for Florida’s “Index Nesting Beach Survey.” (This area is between Amelia Island’s two state parks, Fort Clinch on the north end, and Amelia Island State Park on the south end).

However, the state of Georgia gets only a tiny fraction of nesting sea turtles, compared to the Sunshine State. Florida attracts the majority of nesting loggerhead sea turtles, reportedly 90%, in the USA each year. According to nesting data published by the FWC/FWRI Statewide Nesting Beach Survey Program, Florida recorded 105,164 loggerhead nests year in 2020, 106,373 in 2019, and 91,451 in 2018.

Most of Florida’s loggerhead nesting activity happens on its east coast beaches located further south. “About 80 percent of loggerhead nesting in the southeastern U.S. occurs in six Florida counties (Brevard, Indian River, St. Lucie, Martin, Palm Beach, and Broward Counties),” according to the North Florida Ecological Services office of the U.S. Fish & Wildlife Service. 

Loggerheads don’t reach reproductive maturity until they’re around 30 to 35 years old. Trained volunteers find the nests by scouring the beachfront daily at sunrise, searching for signs of these nighttime visitors. Locally, the Amelia Island Sea Turtle Watch (AISTW) monitors the largest area of Amelia Island’s beachfront. Cumberland’s sea turtle monitoring is done by a team of seasonal interns with the Student Conservation Association, managed by a biologist at the National Seashore. As far as linear miles of shoreline along the Atlantic ocean, Cumberland Island has roughly 22% more east coast beachfront than Amelia.

The Search For Telltale Tracks In The Sand

The trailing turtle tracks left behind in the sand lead volunteers to the buried treasure, the eggs. Each nest is staked and monitored for the remainder of the season. About how many eggs do loggerheads deposit? The number can range from 80 to 120, but the average is closer to around 100.

Hatchlings — Harrowing Odds Of Survival

The odds of sea turtle hatchlings actually surviving to maturity are daunting.  Reportedly only 1% to 3% of sea turtle hatchlings will survive into adulthood, according to scientific estimates.

Green Sea Turtle Nests

This year on Amelia, eight green sea turtle nests have been recorded. However, next door on Cumberland, no green turtles nests have been found this season in 2021, as of mid-September. 

Kemp’s Ridely, World’s Rarest Sea Turtle

A single nest of the rarest species of sea turtle in the world, the endangered Kemp’s Ridley, was recorded on Cumberland Island, GA in 2021. It must have been an exciting discovery, since Kemp’s Ridley nesting beaches are concentrated along the Gulf of Mexico (not happening very often around here at the Florida-Georgia border).

Leatherback Sea Turtles

Occasionally, the biggest of all sea turtles, the enormous leatherbacks, may come ashore to nest, but they’re more rare. No leatherback nests so far this season in 2021 have been recorded on either island.

Nest Hollow Is A Sign Babies Have Emerged

An indication that the tiny sea turtle hatchlings have emerged from a nest is a circular hollow. As shown below, this photo was taken on Amelia Island in August 2021. (Tiny turtle tracks, hard to see in this photo, are also in the sand nearby.)

Sea turtle nest Amelia Island. The circular hole indicates the hatchlings have emerged.
Sea turtle nest, Amelia Island. Hatchlings have emerged. (August 2021)

The tiny hatchlings dig their way out and hopefully head in the correct direction toward the sea. However, light pollution (artificial lights shining from windows and outdoor lighting along beachfront properties), can distract and disorient some of the baby turtles. Unfortunately, there have been times when hatchlings perish after going in the wrong direction.

Sargassum Seaweed – Hatchlings Hide & Eat

Many beachcombers at one time or another, have seen Sargassum seaweed when it washes up at the seashore. But some may not realize how important this seaweed is in the lifecycle of sea turtle hatchlings. Once they reach the sea, Sargassum becomes their safe haven.

Sargassum seaweed on beach, Amelia Island Living photo, Fernandina Beach, Florida.
Sargassum Seaweed, Amelia Island, FL (Photo: AmeliaIslandLiving.com)
Sargassum, A Natural Shelter

This type of seaweed (A.K.A. brown algae), is critical to sea turtle hatchlings. It’s not only a source of food, but also acts as cover — to hide from predators in the ocean. In the photo above, what looks like little berries actually are buoys. These tiny floats are known as pneumatocysts. Filled with gas, they help keep Sargassum adrift in the ocean. However, there are times when large amounts of Sargassum seaweed washes up on beaches (as seen on Amelia Island, pictured below).

Sargassum seawood on Florida beach. Amelia Island Living magazine seashore photo.
Sargassum Seaweed, Amelia Island, FL Beach
Relocated Sea Turtle Nests

On Amelia Island’s south end, a beach nourishment and dredging project this year during sea turtle season 2021 required relocating many nests. A large pipeline and construction activity on the beachfront within the 3.2 mile South Amelia Island Shore Stabilization Association area has required moving 47 sea turtle nests further north on the island, as of mid-September.

South Amelia Island Shore Stabilization Project, photo Amelia Island Plantation area. September 2021 beach news.
South Amelia Island Shore Stabilization Project

For those wondering whether relocating the eggs to a nest dug by a volunteer (instead of the natural, original one dug by a female turtle), impacts a nest’s success, the answer appears to be no. As long as it’s carefully moved within the first 24 hours and closely replicated. According to the Amelia Island Sea Turtle Watch website, they do their best to re-create the new nest to be “similar in size and depth for the number of eggs moved.”

Sea Turtles Are Amazing Navigators

One of the most fascinating things about sea turtles is how they can navigate back to the beach of their birth after 30 years, or more to nest. (As mentioned above, in the case of the loggerhead species, they don’t reach reproduction age until around 30 to 35 years old.) Quite a feat after all those years swimming around in the ocean traveling thousands of miles.

How do they do it? Scientists think they use the earth’s magnetic field. One published study suggests loggerheads “likely imprint on the unique magnetic signature of their natal beach.” (Research by J. Roger Brothers & Kenneth J. Lohmann). Later in life they use this imprinted info to get back to the area of their birth.

During one nesting season, a single female loggerhead sea turtle often nests more than once. They return to the beach (after about a two week or so gap), and dig a second one (sometimes a third or more, as well). Then the female skips two or more years before the next time they nest.

Nest Inventories Taken After Emergence

Here on Amelia Island, three days after a nest has naturally emerged, Amelia Island Sea Turtle Watch volunteers excavate each nest and record various types of data. They count total number of eggs, how many hatched (vs. how many did not), and gather more data, as well. Sometimes one or more babies are discovered still alive in the nest. If observed to be healthy, they are released to the sea.

Watch a Sea Turtle Nest Excavation

Nest excavations on Amelia Island typically are scheduled starting in mid-July at either 7 a.m. or 7 p.m., and continue into Sept./October (fewer happen later in the season). For more info about sea turtles and local nest excavation schedule, see the Amelia Island Sea Turtle Watch website. The organization also has a Facebook group, where they share lots of photos, info and updates.

Two Snug Islands At The Florida-Georgia Border, But Vastly Different

While geographically close, a big difference that separates Amelia Island and Cumberland Island is the amount development that has occurred on each barrier island during the past century.

Cumberland Island remains largely wild and empty, far less touched by human occupation than its Florida neighbor. Most of Cumberland was preserved in 1972, when over 36,000 acres of barrier island and salt marsh became protected as a newly established National Seashore. Daily visitors are capped to just 300 people per day.

Cumberland Island National Seashore’s annual visitation during the past decade has ranged annually between around 50K to 60K, far less than its next door neighbor. On the opposite side of the St. Marys River, Amelia Island is brimming with homes, hotels, restaurants, stores, schools, churches and other types of residential and business development.

As a beach getaway destination, Amelia Island and its historic city of Fernandina Beach attracted nearly one and a half million visitors in 2019, a pre-pandemic estimate published in report by the Amelia Island TDC. (This includes overnight stays, day trippers, and those visiting friends and family). Looking at local visitor growth, back in the year 2000 Amelia Island visitation was estimated at 755,400, compared to 1,458,100 in 2019.

Sea turtle nesting coincides with the height of the busy summer beach season on Amelia Island. Some beachgoers dig deep holes, leave behind trash as well as beach gear when they depart, things that can become an obstacle course for sea turtles at night. The efforts of the Amelia Island Sea Turtle Watch helped fuel some changes over time. They are the prominent advocates and public educators who teach the community and visitors about sea turtles. Five years ago, a “Carry Off” beach ordinance better regulated Amelia Island’s seashore, addressing the issue of leaving things like beach chairs and umbrellas on the beach.

Since Florida attracts the majority of nesting loggerhead sea turtles in the USA, educational outreach is extremely important. Informing coastal residents and visitors about how they can help sea turtles has been a mission in beachfront communities throughout Florida, with help from sea turtle volunteers.

How To Help Sea Turtles When Visiting Beach

Some ways everybody can help are noted below.

Save sea turtles, how to help at the beach. Amelia Island Living magazine.
“Carry Off” Beach Ordinance, Amelia Island

When visiting Amelia Island beaches, please follow the golden rule of “carry on, carry off,” or risk losing your beach gear. The “carry off” beach ordinance first went into effect in June 2016 and states:

“Nassau County Ordinance No. 2016-06 prohibits and regulates personal property left unattended on Atlantic Beach oceans within the unincorporated areas of Amelia Island. Personal items left unattended on the unincorporated area of the County beach from 8:00 p.m. until 6:00 a.m. will be declared a public nuisance and will be removed and destroyed. Personal property includes but is not limited to: tents (including tent frames), cabanas, umbrellas and other shading devices, beach chairs, and other furniture such as picnic tables, tiki huts, volleyball nets, hammocks, floats, sailboards, surfboards, kites, jet skis, sailboats, water cycles, and other watercraft, beach toys, grills, nets, coolers, canoes, kayaks, and general items for beach recreation.”

Amelia Island Beach Driving — Vehicular Traffic

During sea turtle season, no vehicles can be parked on the beaches at night after 9 p.m. or before 6 a.m. An additional local beach ordinance change that impacted Nassau County’s beachfront driving on Amelia Island went into effect in October 2020. The new beach ordinance now restricts who can drive a vehicle onto the beach at County parks. The new law slimmed down car/truck access to only Nassau County residents (with a few exceptions). Additionally, Nassau County’s beach driving access points now have gated entrances with manned security booth where IDs are checked to verify residency (or exemption). (Read related article for more details about Amelia Island beach driving ordinance in Nassau County.)

Nests Washed Away By Ocean

The ocean itself can cause the loss of many nests in one fell swoop. Nor’easters, tropical storms, and hurricanes cause higher tides and churning seas. These conditions often erode the beachfront, changing its surface and washing away sea turtle nests and their eggs.

Predators

On both Cumberland and Amelia, predators can occasionally disturb nests to get at the eggs, such as native ghost crabs. On Cumberland Island, two non-native predators are feral hogs and coyotes. Some coyotes have gotten into Amelia Island sea turtle nests, as well. However, nest losses from predators on both islands is only a tiny percentage (in the one percent range this year).

Who To Call For Sea Turtle Help

If you think you’ve found a struggling or stranded sea turtle locally (or disoriented sea turtle hatchlings), contact the Amelia Island Sea Turtle Watch at 904-583-1913. Or if anywhere in Florida, call FWCC’s 24-hour Wildlife Alert Number at 1-888-404-FWCC (1-888-404-3922).