They are the only species of sea turtle that lack scales. Their shell carapace consists of small, interlocking dermal bones beneath the skin that overlie a supportive layer of connective tissue and fat and the deeper skeleton.
Their carapace has seven ridges along its length and tapers to a blunt point. Their front flippers are proportionally longer than in other sea turtles and their back flippers are paddle-shaped. Both their rigid carapace and their large flippers make the leatherback uniquely equipped for long distance foraging migrations.
Leatherback sea turtles undertake the longest migrations between breeding and feeding areas of any sea turtle, some averaging 3, miles each way. They spend most of their lives in the ocean, but females leave the water to lay eggs.
Leatherbacks are strong swimmers and can dive to depths of approximately 4, feet—deeper than any other turtle—and can stay down for up to 85 minutes. Leatherbacks lack the crushing, chewing plates characteristic of other sea turtles that feed on hard-bodied prey. Instead, they have pointed tooth-like cusps and sharp-edged jaws that are perfectly adapted for a diet of soft-bodied open ocean prey such as jellyfish and salps.
A leatherback's mouth and throat also have backward-pointing spines that help retain gelatinous prey. Leatherbacks occur in the Atlantic, Pacific, and Indian Oceans. Nesting beaches are primarily located in tropical latitudes around the world.
Leatherbacks occupy U. Virgin Islands. Leatherbacks have been satellite tagged at sea on foraging grounds off Nova Scotia, Canada and tracked to nesting beaches in the Caribbean.
Eastern Pacific leatherbacks, on the other hand, nest along the Pacific coast of Mexico and Costa Rica, and forage in the south-central and eastern tropical Pacific Ocean. Leatherback turtles grow faster than hard-shelled turtles. However, there is uncertainty about the age at which they reach sexual maturity. Average estimates range from 9 to 20 years of age. Likewise, little is known about their life expectancy, but they are likely long-lived, with longevity estimates of 45 to 50 years, or more.
Female leatherbacks nest at night on tropical and subtropical beaches. A nesting leatherback will disturb a huge area on the beach and leave behind long, circling tracks. Satellite tagging studies of leatherbacks from the Western Pacific indicate that turtles that nest during different times of the year have different migration patterns.
Summer nesting turtles July through September have tropical and temperate northern hemisphere foraging regions, while winter nesters November through February traverse to tropical waters and temperate regions of the southern hemisphere. Female leatherbacks return to nest every 2 to 4 years. Leatherbacks nest several times during a nesting season, typically at 8- to day intervals and lay clutches of approximately eggs.
The eggs incubate approximately two months before leatherback hatchlings emerge from the nest. The primary threat to sea turtles is their unintended capture in fishing gear which can result in drowning or cause injuries that lead to death or debilitation for example, swallowing hooks or flipper entanglement.
The term for this unintended capture is bycatch. Sea turtle bycatch is a worldwide problem. Historically, sea turtles including leatherbacks were killed for their meat and their eggs were collected for consumption.
Presently, leatherback turtles are protected in many countries, but in some places, the killing of leatherbacks and collection of eggs continue. Coastal development and rising seas from climate change are leading to the loss of nesting beach habitat for leatherback turtles.
Human-related changes associated with coastal development include beachfront lighting, shoreline armoring, and beach driving. Shoreline hardening or armoring e. Artificial lighting on and near nesting beaches can deter nesting females from coming ashore to nest and can disorient hatchlings trying to find the sea after emerging from their nests.
Various types of watercraft can strike leatherback turtles when they are at or near the surface, resulting in injury or death. Vessel strikes are a major threat near ports and waterways, and adjacent to highly developed coastlines. Vessel strikes are a significant cause of leatherback strandings in the eastern United States. Increasing pollution of nearshore and offshore marine habitats threatens all sea turtles and degrades their habitats. The Deepwater Horizon oil spill was the largest offshore oil spill in U.
Ingestion of marine debris is another threat to all species of sea turtles. Leatherback turtles may ingest fishing line, balloons, plastic bags, floating tar or oil, and other materials discarded by humans which they can mistake for food.
They may also become entangled in marine debris, including lost or discarded fishing gear, and can be killed or seriously injured. For all sea turtles, a warming climate is likely to result in changes in beach morphology and higher sand temperatures which can be lethal to eggs, or alter the ratio of male and female hatchlings produced.
Rising seas and storm events cause beach erosion which may flood nests or wash them away. Changes in the temperature of the marine environment are likely to alter the abundance and distribution of food resources, leading to a shift in the migratory and foraging range and nesting season of leatherbacks.
A Memorandum of Understanding outlines our specific roles: NOAA Fisheries lead the conservation and recovery efforts for sea turtles in the marine environment, and the U.
FWS lead conservation and recovery efforts for sea turtles on nesting beaches. We conduct various research activities on the biology, behavior, and ecology of leatherback sea turtles. The results of this research are used to evaluate population trends, inform conservation management strategies, and to assess progress toward recovery for this imperiled species.
Our work includes:. Reduce marine debris and participate in coastal clean-up events. Responsibly dispose of fishing line - lost or discarded fish line kills hundreds of sea turtles and other animals every year. Trash in the environment can end up in the ocean and harm marine life. Reduce plastic use to keep our beaches and oceans clean—carry reusable water bottles and shopping bags.
Refrain from releasing balloons —they can end up in the ocean where sea turtles can mistake them for prey like jellyfish or become entangled in lines. Learn more about marine debris. If interested, attend organized sea turtle watches that know how to safely observe sea turtles. Never feed or attempt to feed or touch sea turtles as it changes their natural behavior and may make them more susceptible to harm.
Boat strikes are a serious threat to sea turtles. When boating, watch for sea turtles in the water, slow down, and steer around them. If you encounter them closer than 50 yards, put your engine in neutral to avoid injury. Learn more about our marine life viewing guidelines. Beaches are paramount for healthy sea turtle populations since females come to the shore to deposit their eggs into nests. Keep nesting beaches dark and safe at night. Turn off, shield, or redirect lights visible from the beach—lights disorient hatchlings and discourage nesting females from coming onto beaches to lay their eggs.
After a day at the beach, remove recreational beach equipment like chairs and umbrellas so sea turtles are not entrapped or turned away. Also, fill in holes and knock down sandcastles before you leave—they can become obstacles for nesting turtles or emerging hatchlings.
Do not drive on sea turtle nesting beaches —vehicles can deter females from nesting, directly strike hatchlings and nesting turtles, damage incubating nests, and create ruts that prevent hatchlings from reaching the sea.
If you see a stranded, injured, or entangled sea turtle, contact professional responders and scientists who can take appropriate action. Numerous organizations around the country are trained and ready to respond. Learn who you should contact when you encounter a stranded or injured marine animal.
This initiative is a concerted, agency-wide effort launched in to spotlight and save the most highly at-risk marine species. Pacific leatherback sea turtles are genetically and biologically unique. Pacific leatherback populations have plummeted in recent decades—Western Pacific leatherbacks have declined more than 80 percent and Eastern Pacific leatherbacks have declined by more than 97 percent.
Extensive turtle and egg harvest and bycatch in fishing gear are the primary causes of these declines. Leatherbacks are listed as endangered under the Endangered Species Act. The Pacific leatherback continues to decline.
The dire status for Pacific leatherbacks make them a priority for recovery and conservation efforts within NOAA Fisheries and with our partners worldwide to stabilize and prevent extinction of this iconic species.
Pacific leatherbacks are split into two populations—Western Pacific and Eastern Pacific—based on range distribution and biological and genetic characteristics.
Western Pacific leatherbacks nest in the Indo-Pacific region and migrate to the tropical waters of the Indonesian seas, the South China Sea, Malaysia, the Philippines, and throughout the temperate waters of the North Pacific, including areas of open ocean in the central North Pacific and coastal areas off the west coast of the United States, as well as to southeastern Australia and New Zealand.
Eastern Pacific leatherbacks nest along the Pacific coast of Mexico and Costa Rica and migrate south to foraging grounds off South America. Pacific leatherbacks are considered one of the most at-risk species because of the drastic decreasing trend since the s. Western Pacific leatherbacks have declined more than 80 percent and Eastern Pacific leatherbacks have declined by more than 97 percent.
More recent trend analyses, on the primary nesting beaches in both the East and West Pacific, continue to show declines. Leatherbacks are pelagic open ocean animals, but they also feed in and migrate through coastal waters. Colour The species carapace shell is dark with white spots. Breeding Female leatherbacks may lay 4 to 5 times per season, each time depositing 60 to eggs.
Leatherbacks appear to nest once every two or three years with an incubation period of approximately 60 days. Diet The large size of leatherbacks is all the more remarkable given their low energy, low protein diet of soft-bodied creatures such as jellyfish, squid and tunicates "jelly fish-like" marine invertebrates.
Previous Population and Distribution The global population for this species was estimated to be , adult females in By this had been revised down to about , Leatherback populations in the Pacific and Indian Oceans have undergone dramatic declines in the past forty years. For example, the nesting colony at Terengganu, Malaysia went from more than 3, females in , to 20 in , to just 2 in - there are no signs of recovery.
Numbers of females recorded at four formerly major Pacific rookeries have declined to about in Mexico, in Costa Rica, two in Malaysia, and fewer than in Indonesia. The Pacific may now have as few as 2, adult females. Effective Protection However, not all leatherback populations have declined: in southern Africa, three decades of strong protection have increased the small annual nesting population more than fourfold.
Recent reports mention that west Africa has an important population with around 10, nests per season, but the total area occupied for the leatherbacks is not well known and there is no available historical information on nesting trends of this population. The most important nesting beaches now remaining in the Atlantic are found in Suriname, French Guiana, and Gabon.
In the Pacific, the few remaining important beaches are in Indonesia, Mexico and Costa Rica, with other rookeries found in Nicaragua, Panama and Guatemala. Indonesia has pledged to protect a top leatherback turtle nesting site. What are the main threats? This has been recognized as the main cause together with fisheries mortalities and poor hatcheries practices for the collapse in the Malaysia population.
There are now few large populations from which eggs could be collected in the western Pacific. Bycatch of manta ray Manta birostris and leatherback turtle Dermochelis coriacea. French Tuna purse-seine fishery in the Atlantic ocean. What is WWF doing?
WWF is working to conserve leatherback turtles and their habitats in Central and South America, and the western Pacific through concerted pan-Pacific and trans-Atlantic approaches that aim to protect critical nesting beaches and migratory pathways. Hatchlings have white blotches on carapace. Size: 4 to 6 feet — cm. The largest leatherback ever recorded was almost 10 feet cm from the tip of its beak to the tip of its tail and weighed in at 2, pounds kg. Diet: Leatherbacks have delicate, scissor-like jaws.
Their jaws would be damaged by anything other than a diet of soft-bodied animals, so they feed almost exclusively on jellyfish. It is remarkable that this large, active animal can survive on a diet of jellyfish, which are composed mostly of water and appear to be a poor source of nutrients.
Habitat: Primarily found in the open ocean, as far north as Alaska and as far south as the southern tip of Africa, though recent satellite tracking research indicates that leatherbacks feed in areas just offshore. Known to be active in water below 40 degrees Fahrenheit, the only reptile known to remain active at such a low temperature. Nesting: Nest at intervals of 2 to 3 years, though recent research has indicated they can nest every year. Nests between 4 to 7 times per season, with an average of 10 days between nestings.
Lays an average of 80 fertilized eggs, the size of billiard balls, and 30 smaller, unfertilized eggs, in each nest.
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