Reptiles of North Carolina

Scientific Name:	Common Name:		Family (Alpha):

NC Records
Sole representative of Dermochelyidae in NC
Dermochelys coriacea - Leatherback Sea Turtle

Photo: Todd Pusser

Taxonomy

Class: Reptilia

Order: Testudines

Family: Dermochelyidae


Taxonomic Comments: Dermochelys is a monotypic genus and the only member of its family
Species Comments: Based on molecular analysis, there do not appear to be any distinct subspecies across the entire world-wide range of this species (Ernst and Lovich, 2009).

Identification

Basis for Records: Good quality photographs of this species are sufficient for its identification.

Field Marks: Adults of this sea turtle are enormous, possessing flippers but lacking scutes, and have a blackish skin that is often marked with pale blotches (Palmer and Braswell, 1995)

Morphological Features: This very large turtle lacks scutes and is covered in thick leathery integument with seven ridges running longitudinally down its back

Technical Reference: Palmer and Braswell (1995); Ernst and Lovich (2009)

Field Guide Descriptions: Beane et al. (2010); Powell et al. (2016)

Online Photos: Google iNaturalist GBIF

Observation Methods: According to Todd Pusser (2023-10-16): leatherbacks are occasionally seen on pelagic birding trips, but the best viewing opportunities are actually from shore. Each spring, in late April through May, leatherbacks make their way into the inshore waters off SE NC, following large cannonball jellyfish swarms. With patient observing, you can spot a leatherback from any fishing pier from Topsail Island down to the SC state line. Of course this depends on the viewing conditions...calm winds equal calm seas, which allows you to detect them much easier as they surface for air. The key is to follow the cannonball jellyfish swarms, which vary in density and distribution each year. In May, during the last decade or so, leatherbacks have been regularly seen off our southern fishing piers, especially those off Wrightsville Beach, Kure Beach, and Topsail Island. In October, at least for the past 10 years, leatherbacks show up along the northern Outer Banks and can be seen feeding on cannonball jellyfish swarms close inshore. I photographed at least 12 different individuals last Wednesday and Friday from Jennette's Pier in Nags Head. They are being seen off Avon Pier now as well. Also last week, the owner of the Coastal Helicopters out of Manteo, counted 25 in a single flight off Pea Island.

Distribution in North Carolina

Distribution Comments: Leatherbacks have been observed along the entire coast of North Carolina (Palmer and Braswell, 1995). Palmer and Braswell knew of only one apparent nesting occurrence but several more nests or nesting females have been observed since then (see Rabon et al., 2002), with one nest observed in 2023 (https://www.newsobserver.com/news/state/north-carolina/article276749751.html).
Distribution Reference: Palmer and Braswell (1995); NCMNS Herpetology Collection Database (accessed 2023-01)
County Map: Clicking on a county returns the records for the species in that county.

Key Habitat Requirements

Habitat: Leatherbacks are pelagic, marine species that are regularly seen offshore of North Carolina. We have only a few records of them nesting in the state, however, and adults may be only transients off our coast. Records are rare from the sounds.

Environmental and Physiological Tolerances: This species may be unique among turtles in that it can maintain its body temperature well above that of the surrounding ocean waters. This thermoregulatory ability allows it to reach latitudes farther north than another other sea turtle. In the western Atlantic, this species ranges as far north as the waters off of Nova Scotia and Newfoundland, with a major foraging area located at the mouth of the St. Lawrence River (Ernst and Lovich, 2009). In the eastern Atlantic, it reaches the waters off of Iceland and Norway; in the Pacific it reaches as far north as the waters off of Alaska.

Biotic Relationships: Leatherbacks feed primarily on Cnidarians, including jellyfish (Scyphozoans) and Portugese-men-of-war (Hydrozoans) (Palmer and Braswell, 1995). Canonball Jellyfish (Stomolophus meleagris) are especially important prey used off our coast. Other invertebrates and fish are also eaten, as are seaweeds. Their preference for transparent Cnidarians has led to their ingestion of large quantities of plastic bags, which they cannot digest or easily eliminate, causing blockage of their digestive systems.

Eggs and hatchlings are heavily predated, running a gauntlet of Ghost Crabs, gulls, crows, and other predators just to reach the ocean where they are then preyed upon by squid and a number of fish species (see Ernst and Lovich, 2009, for a long list of predators). Large adults are fairly immune from predation, but may be attacked by large sharks or Orcas.

Life History and Autecology

Breeding and Courtship: Females reach reproductive maturity at 6-15 years (Ernst and Lovich, 2009). Males mature at about the same body sizes as the females. In the tropics, mating takes place just before nesting, but in temperate areas mating probably takes place before the start of northward migration.

Reproductive Mode: Females show nesting site fidelity, ovipositing preferentially on beaches where they have nested before (Ernst and Lovich, 2009). Beaches lacking abrasive materials are preferred, avoiding with rough substrates and/or debris that could damage the skin of the females. Nests are usually excavated within 15 meters of the high tide mark. A given females nests multiple times, with a mean of 5.6 and a range of 1-11 (Ernst and Lovich, 2009). In Florida, females nest at 8-12 day intervals. The typical clutch contains a mean of 77 eggs, with a range of 23-166. Females nest every 2-4 years.

Aquatic Life History: This species is completely pelagic, with only the females coming to shore to nest. While some populations are fairly sedentary -- the population off of Florida is present year round -- this species follows the migration of flotillas of jellyfish and is only transiently present in the waters off of North Carolina.

Terrestrial Life History: Like other turtles, leatherbacks are tied to land only for nesting. Following hatching, juveniles must move across the beach as fast as they can to avoid the myriad predators that are waiting for them. Once they reach the water, they also swim in a burst of high speed, taking them as quickly as possible away from the inshore waters where they are also highly vulnerable to predation.

General Ecology

Adverse Environmental Impacts

Habitat Loss: Loss or degradation of nesting beaches due to beachfront development is a major cause for concern. Nests can be destroyed by vehicles driving on the beaches and outdoor lights at night can severely disrupt the ability of hatchlings to orient correctly to the ocean, a perilous journey as is.

Effects of Pollution: Oil spills can have a major impact on the survival of this species as can runoff of agricultural chemicals and their impacts on water quality. Plastic pollution is by itself one of the major impacts to this species, which ingests large quantities of the plastic bags it mistakes for jellyfish.

Interactions with Humans: Eggs are heavily harvested in many areas of the world. Habitat loss due to beach front development is a major factor everywhere within the range of this species, strongly affecting nesting success. Adults become entangled in fishing gear and are hit by boats. Ingestion of plastic bags was mentioned previously and water pollution -- particularly from oil spills -- is a significant source of mortality. Global warming -- particularly rises in sea temperatures -- is likely to become ever more concerning and increasingly large tropical storms are likely to devastate nesting beaches. As with many other turtle species, sex determination in this species is temperature dependent and rising temperatures may make males a very scarce portion of the population. These impacts are summarized by Ernst and Lovich (2009), who paint a very grim picture of the chances of this species surviving over the next century.

Status in North Carolina

NHP State Rank: S1B,SUN

Global Rank: G2G3

Status in North Carolina: E

Global Status: E

Protected Lands: In North Carolina, nesting has been observed primarily along the Cape Hatteras and Cape Lookout National Seashores, where protection of their nests has a high priority.

Environmental Threats: Global climate change threatens this species in several ways. The ocean temperatures in the tropics may rise so far as to threaten the survival of both this species and the prey species it feeds on. Massive tropical storms are already known to have destroyed entire nesting beaches and are likely to do even more such damage in the future. Leatherbacks, like other turtles, have sex determination that is dependent on the temperatures present in their nests. With rising global temperatures, males -- which require relatively cool temperatures to develop -- may become increasingly scarce.

Status Comments: This magnificent species is considered Endangered throughout its world-wide range.

Stewardship: Protection of nests and guiding of hatchlings to the sea can both help raise the chances of survival of this species, as can reducing the amount of night-time lighting in beachfront development. Reducing the impacts of fishing gear entanglement, accidental capture by trawlers, and collisions with boats are other measures that would help this species, as would bans on the use of plastic bags particularly in areas along the coast where they are most likely to wind up in the sea.

Photo Gallery for Dermochelys coriacea - Leatherback Sea Turtle		4 photos are shown.
	Recorded by: Todd Pusser Dare Co. Comment:	Recorded by: Todd Pusser Dare Co. Comment:
	Recorded by: Todd Pusser Dare Co. Comment:	Recorded by: Todd Pusser Dare Co. Comment:

Dermochelys coriacea - Leatherback Sea Turtle

Photo Gallery for Dermochelys coriacea - Leatherback Sea Turtle

4 photos are shown.