There are seven species of marine turtle
Marine turtles existed almost 100 million years ago, and they coexisted with dinosaurs. Scientists now recognise seven different types of marine turtles:
Six of these are endangered, and there isn't enough information on the flatback to determine how endangered it is.
Green sea turtles are green because of their diet
Green sea turtles are the only sea turtles that are predominantly herbivores, feeding mostly on seagrasses and algae. This diet is responsible for the greenish colour of their cartilage and fat (not their shells), which is how they got their name.
Sea turtles dig a nest in the sand with their back flippers to lay their eggs
Sea turtles normally lay 100-125 eggs (a clutch) per nest and will nest numerous times over the course of several months, about two weeks apart. The hatchlings dig out of their nest as soon as the eggs hatch (about 2 months later). This procedure usually takes a few days to complete. The little turtles dash to the sea and make their way offshore into the wide ocean as soon as they emerge. Sea turtles are threatened by a variety of factors, but those that survive to adulthood are decades old.
The temperature of the sand is critical
The temperature in the nest determines the sex of sea turtles, as it does many other turtles. Male hatchlings are produced by cooler incubation temperatures, while female hatchlings are produced by warmer incubation temperatures. Temperatures that swing between the two extremes result in a mixture of male and female hatchlings.
Hawksbill turtles use their beaks to assist in the extraction of their preferred prey.
Hawksbill turtles are most commonly found in coral reefs, which are home to their favourite food: sponges. Their beak's shape and sharpness allow them to reach into small holes and crevices on coral reefs in search of food.
Turtles are the lawnmowers of the seas
Green sea turtles eat seagrass and have a more plant-based diet. They prevent seagrass from growing too tall and injuring other marine organisms by keeping it short.
Marine turtles can hold their breath underwater for up to five hours
In order to conserve oxygen, they reduce their heart rate to up to nine minutes between heartbeats.
Turtles do not have teeth
Their meal is grasped with their beak-like mouth. Keratin is used to make this beak (the same stuff your fingernails are made of).
They can grow extremely large
The size of marine turtles varies widely. Kemp's ridleys are the smallest, measuring roughly 70cm long and weighing up to 40kg, while leatherbacks can grow to be 180cm long and weigh 500kg. That's a tenfold increase in weight! Wales has the world record for the largest sea turtle ever discovered. A leatherback measuring 2.5 m long, 2.5 m from flipper to flipper, and weighing over 900kg (more than 140 stone) was discovered ashore in 1988!
One type of sea turtle lays its eggs during the day
Most sea turtles lay their eggs at night; Kemp's ridleys are the only ones who lay their eggs during the day.
Leatherback sea turtles have been around since the time of the dinosaurs in their current form
Leatherback turtles are migratory, swimming over 10,000 kilometres between nesting and foraging locations each year. They are also skilled divers, with the deepest dive ever recorded reaching over 4,000 feet, which is deeper than other marine mammals. They have prickly "papillae" surrounding their mouth and oesophagus, which assist them catch and eat jellyfish, which is their major meal.
Loggerhead turtles spend the first 7 to 15 years of their existence (on average 12 years) in the open ocean
They then relocate to near-shore coastal habitats, where they will continue to develop and grow. Researchers have revealed that loggerhead turtles in the Pacific have a highly migratory life stage thanks to satellite surveillance. Hatchlings from Japan and Australia's nesting beaches make their way into the ocean. Some individuals migrate across the Pacific Ocean to feeding sites off the coasts of Baja California, Mexico, Peru, and Chile as part of their growth process. That's almost 8,000 kilometres!
Sea turtles do not retract into their shells when they are threatened
Sea turtles, unlike other turtles, do not have the ability to withdraw their flippers and head within their shells. They are exceptionally agile and graceful swimmers due to their streamlined shells and huge paddle-shaped flippers. Their back flippers are utilised as rudders to steer in the water.