Endangered: The Leatherback Sea Turtle Quiz

Answer: Arctic Ocean

The leatherback sea turtle has the largest distribution range of all reptiles, and possibly of all vertebrates. They have what is called a "cosmopolitan" range, which means they can be found everywhere in the world a suitable environment can be found. Adult specimens can sometimes be found as far north as Alaska, and as far south as New Zealand. You would be most likely to find one in the tropical or subtropical waters of the Pacific, Indian, and Atlantic oceans.

The three largest distinct populations of the turtle can be found in the Atlantic, and the east and west of the Pacific.

Answer: Cretaceous

The leatherback sea turtle is the only surviving member of the Dermochelyidae family. This family has existed in some form since the Cretaceous Period, 110 million years ago. Their closest living relatives are the Chelonioidea, which includes the other sea turtles, and the Protostegidae, which died out in the Mesozoic Period but included some other leatherbacks.

The first to name the species was Domenico Agostino Vandell in 1761, who gave it the name "Testudo coriacea". This was changed to "Dermochelys coriacea" (as it is now) after Henri Blainville created the term "Dermochelys". Then in 1843 they were moved to their own family, Dermochelys, by Leopold Fitzinger.

The Jurassic and Triassic periods were both earlier in the Mesozoic Era than the Cretaceous Period, while the Holocene began in the Cenozoic Era and still continues today.

Answer: Yes

The leatherback sea turtle is the largest of the turtle species, and the fourth largest reptile species, just behind three crocodiles. They can grow an incredible two metres (seven feet) long and can weigh over 900 kilograms (2000 pounds)! The largest recorded specimen was an adult male found on a beach in Wales.

It measured over three metres (9.8 feet) in length and weighed 916 kilograms (2020 pounds)!

Answer: Longest lifespan of any reptile

As well as being the largest turtle and the fourth largest reptile and having the largest distribution range of all reptiles, the leatherback has many other records to its name.

Leatherbacks have been recorded to reach depths of 1280 metres (4200 feet), which means they are the deepest divers of the reptiles. Typically, however, a dive takes about 3-8 minutes, and anything longer than that is rare. They can hold their breath for up to 85 minutes before they have to surface.

The leatherback sea turtle typically moves at about 0.5-2.8 metres (1.6-9.1 feet) per second, or 1.1-10.08 kilometres (0.7-6.3 miles) an hour. However, they have been recorded to reach speeds of 35.28 kilometres (21.92 miles) per hour, which means they are the fastest moving reptile, according to "Guinness World Records" (1992).

The front flippers of a large adult leatherback sea turtle can reach lengths of 2.7 metres (8.9 feet). This makes them the largest flippers of any sea turtle, both in size and when compared to their body size.

While it is unknown exactly how long the leatherback sea turtle lives, the estimated lifespan is 45 years. The longest living reptile title goes to the Galápagos tortoise, with a lifespan of over 100 years.

Answer: Thick layer of blubber

In order to survive the cold waters, the leatherback sea turtle has made many adaptations. For example, they have a thick layer of fat (not blubber, which is found in whales, seals etc.) to help insulate them. They are also constantly moving, with records of turtles resting for less than 0.1% of the day! This helps keep their muscles warmer. They also use strategic changes in their blood flow and their large body size to help regulate body temperatures. This large body size mechanism is referred to as "gigantothermy", and it was possibly also used by dinosaurs, and is still used by many other animals, such as the great white shark. They also use a special way of generating heat from chemical reactions in their body, called "endothermy".

The leatherback sea turtle lacks a shell, and instead has an oily and skin-covered back with ridges which gives it its name. This is a distinctive feature of the species. Another distinctive feature is that it lacks scutes, instead it has leathery skin. Its body is well streamlined and tear-shaped, helping it to move gracefully through the water. The top of the turtle is black or dark grey, with patches of white, while it has a lighter-coloured belly to assist in camouflage.

Answer: Carnivorous

The leatherback sea turtle is a very fussy eater; it almost exclusively feeds on jellyfish. This is beneficial to humans and the environment as it helps to regulate the jellyfish population. They also feed on squid and other soft-bodied organisms.

The hunting strategy of the leatherback sea turtle is to track their prey throughout the day. This means they often venture in to deeper water earlier in the day, and then go shallower and shallower. They will also migrate to other waters to find more food, such as from Indonesia to California.

A herbivore is an animal that only eats plants, an omnivore is one that eats both meat and plants and a cannibal is an animal that eats its own species.

Answer: Teeth

Leatherback sea turtles lack teeth, like many turtles, but they also lack the ridges characteristic of turtles. Instead, they have sharp beaks with little points on them, and spines which face backwards in their throat. These adaptations are perfect for the soft-bodied food they feed on, such as jellyfish. They certainly do have a tongue, ears and nostrils as well!

Answer: False

Leatherback sea turtles are considered polyandric- this means that a female will mate with many males. Mating occurs at sea, and fertilisation occurs internally. The turtles partake in the longest migration out of all turtles in order to mate, averaging about 6000 kilometres (3700 miles) each way.

The females will then come to shore to lay their eggs. They choose beaches with soft sand as their eggs are soft, and any rocks could break them, and these beaches are often the ones they were born on. The female lays about 110 eggs a time, but not all of them are fertilised (about 85% are).

She'll then return to the water after burying the eggs. A female may lay up to nine clutches per breeding season (which varies with location), with about nine days between each clutch. Once the young break forth from their eggs, they are on their own, and must rush to the water before being caught by predators, including birds and crabs. Even in the ocean, sharks may feed upon the young.

The eggs hatch after about 60-70 days.

The temperature of the nest determines the gender of the offspring- at about 29.5 degrees Celsius (81.5 Fahrenheit) the offspring will be mixed, while warmer temperatures will produce males and cooler temperatures females. It is estimated that only one in 1000 hatchlings will survive until adulthood. Males spend the rest of their life at sea, while females will come to shore to lay eggs.

Answer: Plastic bags

An estimated one third of adults have tried to ingest plastic, particularly plastic bags. They confuse them for their main prey - jellyfish. Some adults have been found with over five kilograms (11 pounds) of plastic inside their stomach. The plastic can block up their intestines or lead to malabsorption of nutrients. They are particularly prone to eating these closer to urban areas, especially around California, which uses up to 19 billion plastic bags a year.

While I'm sure it would be dangerous for the leatherback sea turtles to digest the other options, there is no evidence that this has actually happened.

Answer: Natural predators

The most major threat to the leatherback sea turtle is egg harvesting, particularly in places like Southeast Asia, where the eggs are a delicacy, or the Caribbean where they are considered an aphrodisiac. Egg harvesting and poaching has been a major threat, accountable for removing about 95% of the clutches in some places. Other threats include being caught as bycatch by fishers, with about 1,500 adult females being caught as bycatch in the 1990s. Chemical and physical sea pollution can be dangerous, such as when the leatherbacks attempt to consume plastic, mistaking it for jellyfish. Many adults are caught for their meat and by fisheries, and in some places females are taken from the beach for extracting oil. Leatherback hunts, both traditional and not, also poses a serious threat. Leatherback adults have very, very few natural predators, however the babies are often consumed by predators like birds and small mammals.

The leatherback sea turtle is listed as "Critically Endangered" by the IUCN Red List, the highest risk category of extinction. It is difficult to determine the exact remaining population, but a 1996 estimation shows about 20,000 to 30,000 adult females. While this may seem like quite high numbers, when compared to the fact that there were about 115,000 adult females in 1982, this shows about a 78% drop in just 14 years. In some places the turtle has already gone extinct. Some of the most important hatching places have shown a significant decrease in number, such as with the East Pacific leatherback population, which has dropped from 4,638 adult females in 1995 to 1,690. It is estimated by the IUCN that there has been a decline in Pacific populations by about 80%. Many countries are introducing conservational laws to protect the species, and it is important that they continue to do so, both for their future and for ours.