This story has been updated
By Peter Vankevich
As the 2021 sea turtle nesting season winds down, it turns out to be a very good year once again for loggerhead sea turtles on the Outer Banks and the approximately 330 miles of North Carolina’s sandy ocean beaches.
Here are some of the nesting highlights and facts about sea turtles in North Carolina waters, home to five of the seven species worldwide.
From a sea turtle perspective, coastal North Carolina is loggerhead territory, comprising of 97 percent of all recorded sea turtle nests this season. According to Seaturtle.org, an organization that supports sea turtle research and conservation, a total of 1,496 nests from 25 coastal locations were recorded throughout the state: 1,446 loggerhead, 42 green, seven Kemp’s ridley and one unknown. From these nests, unofficially as of Oct.20, 107,967 hatchlings emerged.
Federal agencies such as the National Park Service, U.S. Fish and Wildlife Service, U.S. Marine Corps, U. S. Army Corps of Engineers, state agencies and nongovernment organizations and individuals input their data to the website.
Since 1983, the N.C. Wildlife Resources Commission has administered the North Carolina Sea Turtle Protection Program to monitor sea-turtle nesting activity in North Carolina and document reproductive success and failures.
The Cape Hatteras National Seashore (CAHA), which includes Hatteras and Ocracoke islands and part of Bodie Island, reported a total of 315 nests, 298 loggerhead, 14 green and three Kemp’s ridley. As of Oct. 19, only seven nests were still incubating and a total of 19,634 hatchlings have already emerged.
Ocracoke has had 97 turtle nests: two green, one Kemp’s ridley and 94 loggerhead. This is the second highest number of nests for the island since records began in the 2000s, with the highest of 147 nests in 2019.
Volunteers to the rescue
Improving nesting success of sea turtles relies heavily on many volunteers. Most receive extensive training from the Network for Endangered Sea Turtles (N.E.S.T.), an all-volunteer non-profit organization dedicated to the protection and conservation of sea turtles and other protected marine wildlife on the Outer Banks.
This was a particularly demanding year because of so many nests. Ocracoke, as with other locations, has welcomed volunteers. More than 1,000 state-wide have participated in nest monitoring activities, which has contributed to this year’s nesting success.
Islander Ruth Fordon has been a turtle-nest volunteer since 2004.
“I’m an early riser which is important because you have to be ready at 5 a.m. to meet with the Park Service staff for the morning turtle patrols,” she said. “I just love going out and riding with them in the morning from South Point all the way up to the north end looking for the tracks and if there is a nest, helping them set up protective enclosures, as well as all the other nest maintenance tasks that occur as the summer progresses.” She is also an evening nest sitter volunteer.
Amy Thompson, Ocracoke’s lead biotechnician for CAHA, has nothing but praise for Fordon. “Ruth’s assistance was absolutely invaluable,” she said. “She was on the morning turtle patrols assisting in the often-labor intensive tasks and with her long experience, provided lots of insights.”
“Everyone on our resource management team loved working with her,” Thompson added.
The patrols also include looking for turtle strandings, which occurred five times this summer when adult loggerheads crawled over the dune line and onto Highway 12 at the north end overwash area.
In the evenings, the volunteer nest sitters make sure the nests are not disturbed and will block out any artificial lighting from nearby buildings with tarps. Light pollution is a serious threat to hatchlings, which have a strong attraction to light. It can cause them to become disoriented and crawl toward the light and away from the beach. People are strongly encouraged to turn off lights that impact the beach. Volunteers will also smooth out the tire tracks between the nest and the water so that hatchlings don’t get trapped in the sand.
Sometimes volunteers have the wonderful opportunity to see the hatchlings emerge, called a boil. They will serve as escorts to protect hatchlings from ghost crabs as they crawl to the ocean.
Once in the water, the hatchlings are on their own and face a new set of dangers — fish, sharks and dolphins, among others.
The hatchlings will swim out to the Gulf Stream, which provides shelter in the floating sargassum weed, a temperate climate and plenty of small organisms that the hatchling can feed on.
Males will remain at sea and females return to land only to nest and at the general location where they hatched.
If they make it past the first few years and avoid the causes for their endangerment, they may live up to 50 years.
It is not only during nesting season that volunteers help sea turtles. In winter, when temperatures drop below 50 degrees for sustained periods, a deadly form of hypothermia will cause sea turtles to wash ashore. Then, volunteers will head out to search for and help rescue these cold-stunned sea turtles, which would otherwise die.
Depending on the season and location on the coast, volunteers may be managed by different organizations. Anyone interested in volunteering to help respond to and monitor sea turtle and marine mammal activity can start by contacting N.E.S.T on its website.
Upward trends in nesting success
The Outer Banks has seen a remarkable trend of increased nesting of loggerhead sea turtles, whose nests have more than tripled since the early 2000s.
The highest year was 2019 with a state total of 2,358 nests of all species (2,293 loggerhead, 63 green and two Kemp’s ridley). An amazing number of 146,888 hatchlings emerged that year. Cape Hatteras National Seashore reported a total of 440 loggerhead, 32 green and one Kemp’s ridley and 28,093 emerged hatchlings.
These high numbers are vital for their survival. Very rough estimates are that only one in 1,000 or more hatchlings makes it to adulthood.
Dangers start immediately upon emerging. A nest-to-surf mortality study of loggerhead sea turtle hatchlings on Florida’s East Coast estimated that 7.6% of the hatchlings did not make it to the ocean. The main predators were ghost crabs, mammals and birds, notably yellow-crowned night herons.
Threats to sea turtles
Historically slaughtered for their eggs, meat, skin, and shells, sea turtles now have protection against these activities, but poaching remains a problem in many areas.
Threats to the survival of sea turtles are many. They include vessel strikes, persistent and abrupt low-frequency noise such as from seismic tests for energy exploration, plastics in the ocean they ingest thinking it is food and accidental capture in fishing gear —known as bycatch. The use of turtle excluder devices (TEDs) in shrimp trawls, gillnet bans, and other gear modifications have reduced sea turtle bycatch but it remains a major cause of mortality.
More research on the impact of climate change is needed, but one known problem is that warmer sand temperatures can affect their future. The sex of a sea turtle is determined by the temperature at which the egg is incubated, with higher temperatures producing more females. Fewer males can diminish nesting success.
North Carolina’s sea turtles
Five species of sea turtles may be seen in North Carolina. Three, Kemp’s ridley, leatherback, and hawksbill are listed as endangered, and two, loggerhead and green, are listed as threatened.
Leatherbacks nested in North Carolina in small numbers in the early 2000s, the most recent were two in 2018. The last one that nested on Ocracoke was in 2012 but no hatchlings emerged.
Leatherbacks are regularly seen traveling along the North Carolina coast in late spring/early summer as they migrate from nesting grounds in the Caribbean to foraging grounds off Nova Scotia, according to Sarah A. Finn, Coastal Wildlife Diversity Biologist with the NC Wildlife Resources Commission. They are also seen on occasion in the winter off the coast, especially around the Gulf Stream.
A dead leatherback was found last January on the sound side of Frisco on Hatteras Island.
The only known hawksbill nests on the Outer Banks occurred in 2015. One was successful and the other was washed out by a nor’easter storm. These turtles are sub-tropical and tropical, and the nests were the most northerly of its distribution range documented in the Atlantic Ocean.
Sea turtles nest more than once per season. So, when you see a report of 97 nests on Ocracoke this year, it doesn’t mean that 97 individual sea turtles nested. In fact, it is probably far fewer. DNA analysis of the eggs which takes time, provides insight as to how many individuals did nest.
Here is some information on the five sea turtles of the Outer Banks.
Loggerhead (Caretta caretta):
Named for their large head, female loggerheads reach maturity at about 35 years of age. Every 2 to 3 years they mate in coastal waters and return to nest on a beach in the general area where they hatched decades earlier.
Loggerheads nest at intervals of 2 to 4 years and lay between 3 to 6 nests per season, approximately 12 to 14 days apart. An average of between 100 to 126 eggs are laid in each nest. Hatchlings emerge in about 60 days.
The successful hatchlings from coastal North America spend years in the Gulf Stream.
Adults vary considerably in size, ranging from 150 to 375 pounds. Loggerheads feed primarily on shellfish. Their range includes the Atlantic, Pacific and Indian Oceans. They forage in coastal bays and estuaries, as well as in the shallow water along the continental shelves. Carnivores, their powerful jaw muscles enable them to feed on hard-shelled prey such as whelks and conch.
Skeletochronology research in the NOAA lab in Beaufort, North Carolina, has shown that loggerhead sea turtles are likely live to be 70 years or older.
Loggerhead turtles are found worldwide primarily in subtropical and temperate regions of the Atlantic, Pacific, and Indian Oceans, and in the Mediterranean Sea. In the Atlantic, the loggerhead turtle’s range extends from Newfoundland to Argentina.
One study conducted many years ago estimated that worldwide, there are between 40,000 and 50,000 nesting females.
Green turtles (Chelonia mydas)
Don’t expect to see green shells on these turtles. They were named for the green color of the fat under their carapaces, i.e., shells. Carapace colors range from brown, olive-and-gray to black.
Females nest at intervals of about every two years and between three to five times per season. They lay an average of 115 eggs in each nest, with the eggs incubating for about 60 days.
Because there are so few nesting females on the Outer Banks, adults are rarely seen, and they are huge — weighing between 240 and 420 pounds — and can be up to four feet in length. Young green sea turtles, weighing in the 10 to 20-pound range, are the most likely species to be seen washed up on shore during cold spells, because many forage in the Pamlico Sound.
Unlike the loggerhead, adult greens are herbivores feeding on subaquatic vegetation and algae. Young sea turtles will also feed on worms, crustaceans and insects. Their jaws are finely serrated, which aids them in tearing vegetation.
Green turtles are found in all temperate and tropical waters throughout the world near coastlines, islands, bays and protected shores with seagrass beds. Rarely are they observed in the open ocean.
The Sea Turtle Conservancy estimates that worldwide, there are between 85,000 and 90,000 nesting females.
Kemp’s ridley (Lepidochelys kempii)
This sea turtle is named after Richard Kemp, a Florida fisherman and naturalist who discovered this species in 1880 and sent the specimen to Harvard University to be studied.
They nest more often than other sea turtle species, every one to three years on average and two to three times each season. They lay an average of 110 eggs in each nest and the eggs incubate for about 55 days.
Their range is mostly limited to the Gulf of Mexico, which explains why so few nest on the Outer Banks.
Much smaller than loggerheads and greens, adults measure around two feet long and weigh between 70 and 108 pounds. Carnivores, they feed on crabs, clams, mussels, shrimp, fish, sea urchins, squid and jellyfish.
On the brink of extinction in the 1960s, they were listed as “endangered” under the U.S. Endangered Species Conservation Act, the predecessor to the U.S. Endangered Species Act in 1970. Efforts to bring them back included clamping down on illegal harvesting and a successful relocation of more than 20,000 eggs from Mexico to Texas over a period of 10 years.
They remain the rarest of the sea turtles but have made a slow but steady increase. Estimates today are between 7,000 and 9,000 nesting females.
Leatherback (Dermochelys coriacea)
This sea turtle gets its name from its unique carapace, which is composed of a layer of tough, rubbery skin, strengthened by tiny bone plates that gives it a leathery look.
Sightings in the region are highly newsworthy, even if found dead, as was the case this past January when one was found on Hatteras Island.
By far, the leatherback is the largest sea turtle and reptile on earth. Adults are four to eight feet in length and most weigh between 500 and 1,000 pounds. The largest leatherback ever recorded, weighed 2,019 pounds with a length of nearly 10 feet from head to the tip of the tail.
Leatherbacks nest at intervals of two to three years, and between four to seven times per season. Incubation of an average of 80 eggs is about 60 days.
Unlike the other sea turtle species that return to where they hatched, females may change nesting beaches, though they tend to stay in the same region.
Their primary food source is jellyfish. Strong swimmers, they can dive to depths of approximately 4,000 feet — deeper than any other sea turtle — and can stay down for up to 85 minutes.
Open ocean wanderers, they have the widest distribution of sea turtles because they can tolerate cold temperatures. In the Atlantic, they can be found as far north as Norway and the Arctic Circle and south to the tip of Africa.
In the Pacific, their range extends as far north as Alaska and south beyond the southernmost tip of New Zealand.
They migrate to tropical and subtropical coastal regions to mate and nest, which explains why they are rare nesters in the Carolinas. In the Atlantic, they nest on beaches of the West Indies and Trinidad and Tobago.
Because of their fondness for jellyfish, they are particularly susceptible to harm caused by ingesting plastic bags and other plastics, which can lead to their death.
Estimates are between 34,000 and 36,000 nesting females.
Hawksbill sea turtle (Eretmochelys imbricata)
Named for their narrow, pointed beak, the hawksbills’ beautifully-colored, patterned carapace is the classic “tortoiseshell” that nearly drove them to extinction as hunters sold the shells to those making jewelry and trinkets.
Today, the Convention on International Trade of Endangered Species (CITES) forbids the trade of any turtle products on the international market, including hawksbill tortoise shell, but illegal hunting continues to represent a threat to the species in many parts of the world.
Hawksbills are found mainly throughout the world’s tropical oceans, which accounts for why they are so rare here, with just one known nesting in 2016 and 10 reports of stranded hawksbill sea turtles since records were kept beginning in the mid-1980s; all were small juveniles, and all were observed between 2001 to 2009, according to a published report.
They nest at intervals of two to four years and between three to six times per season, with an average 160 eggs in each nest.
Adults can weigh up to 150 pounds.
They forage mainly on sponges around coral reefs by using their narrow-pointed beaks to extract them from crevices on the reef. The also eat sea anemones and jellyfish.
In addition to illegal hunting, they are threatened by the deterioration of coral reefs which is linked to climate change.
Population estimates are between 20,000 and 23,000 nesting females.