There are 7 different types of sea turtles in the world and they all have different diets. The type of foods they eat will mostly be determined by their species and age. Each sea turtle species has different natural diets and natural needs that help to keep them healthy.
Sea turtle diet will vary so they can be herbivorous (eat plants), carnivorous (eat meat), or omnivorous (eat both plants and meat) depending on the species, their jaw structure, where they live and the food sources available. Some species will change their eating habits as they grow older. Depending on the species sea turtles might eat algae, jellyfish, seagrasses, squid, sponges, shrimp, cuttlefish, sea squirts, sea cucumbers, or crabs.
The diet of a freshwater turtle will vary and can include water plants, worms, algae, snails, crustaceans, insect larvae, aquatic insects, and fallen fruit. Other freshwater turtles like the snapping turtle will eat fish, frogs, snakes, and even other smaller turtles. Terrestrial turtles also have a variety of foods they can eat like caterpillars, mushrooms, earthworms, beetles, grub, snails, berries, flowers, and fruits. Both land and aquatic turtles have been known to also eat decaying flesh if available.
Sea turtle description
Sea turtles are reptiles so they’re ectothermic meaning they’re cold-blooded, lay eggs, use their lungs to breathe, and have a 3 or 4 chambered heart. These turtles have a carapace that is streamlined to help them swim and a plastron, however, all but one turtle species have a carapace that is covered in hard scutes. Unlike land turtles, sea turtles can’t retreat into their shells. They also have paddle-like flippers to help propel themselves through the water, but they’re not very good for walking on land. They breathe fresh air so they have to come to the surface when they need to get some air and this leaves them vulnerable to being hit by boats or getting caught in the fishing nets.
Behavior
Sea turtles will travel for long distances to feed and nest and even stay in warmer waters when the seasons change. Young turtles will also spend a lot of time traveling between the time they’re hatched and the time they return to the mating or nesting grounds. Most sea turtles take a long time to mature which makes them live for longer with a lifespan of about 70-80 years.
Reproduction and hatchlings
All turtles that live both on land and in the sea lay eggs and sea turtles spend several years out in the sea but go onshore to lay their eggs. It takes sea turtles about 5-35 years to become sexually mature, but this will depend on the species. The males and females will then migrate to their mating grounds near their nesting area.
Sea turtle’s mouth and jaws
The mouths and jaws of sea turtles are shaped differently depending on what they eat. The jaws of the loggerhead turtle are strong and massive which makes it easy to crush hard-shelled prey, while the beak of the green turtle has finely serrated edges like a saw so it can have an easier time tearing seagrasses and algae from the hard sea surfaces. The leatherback’s jaws have sharply pointed cusps that allow them to pierce and hold jellyfish while their sharp, downward curving spines in their mouths and throat help to slide their food into their stomach. The hatchlings have a very different diet from that of the adults. Hatchlings can eat a variety of prey including hydrozoans, larval crabs, jellies, fish eggs, pelagic mollusks, and seaweed.
Different sea turtle species
7 different sea turtle species are found in our ocean waters. While they will periodically move to the shore to bask or lay eggs, sea turtles will spend most of their time in the ocean. They will often make long journeys to specific beaches year after year to lay eggs.
Leatherback turtle
This is the largest sea turtle with a weight of over 2000 pounds and over 6 feet long. This gigantic reptile has a very different look from the other turtles. They have dark skin that is covered by pink and white spots. They can dive deep into the ocean over 3000 feet and swim the farthest that all the other sea turtles. They have a thick leather carapace instead of a hard shell like other turtles and it can survive in cooler waters and this allows it to feed near the north and south poles where other turtles aren’t equipped to survive. You will also find them in waters closer to the shore.
Their ability to adapt to different environments has to do with their internal body heating system and the large amounts of oil in their bodies that keeps their core temperatures higher than their surrounding water. This unique body adaptation allows these turtles to tolerate colder conditions.
These turtles have very weak jaws to chew the hard-bodied prey so they feed on jellyfish, urchins, salps, squid, and crustaceans. Instead of teeth, these turtles have sharp, beak-like cusps that help to grasp their prey while the spines in their mouth cavity and throatthat point backward makes sure their prey don’t exit their mouth and help them swallow the food. Because of the nature of their feeding habits, leatherback turtles often consume marine debris like plastic bags that they mistake for their prey.
Loggerhead turtle
This is the second-largest sea turtle that is capable of coexisting with different marine species that nest mostly in the Florida beaches. It’s a reddish-brown turtle with a very large head and can weigh up to 400 pounds and grow up to 3.5 feet long. This turtle can live in both temperate and tropical waters in the Atlantic, Pacific, and the Indian Ocean and will feed on jellyfish, mollusks, and crabs. The hatchlings are herbivorous while the adults are carnivorous and have a lifespan of up to 67 years.
Green turtle
These turtles are among the endangered species and a fairly large species that weigh up to 400 pounds with a length of about 5 ½ feet. These are graceful and serene swimmers that live in the warm coastal waters of the tropical and subtropical oceans. They have a streamlined shell that covers their whole body except their head and flippers. The adults have a carapace that can be shades of brown, black, gray, and olive with a white to yellow plastron. Green turtles got their name from the greenish color on their fat and cartilage. Sea turtles usually have the mobility of their necks, but they can’t withdraw their heads into their shells.
The adults feed on salps, sponges, and jellyfish, but they mostly eat plants like algae and seagrass that’s why their fat has a green color pigment from the green diet, hence the name. These turtles have finely serrated jaws to help them with their herbivorous diet.
Hawksbill turtle
This turtle is also among the endangered species. These are small to medium-sized turtles that can weigh up to 200 poundsand grow up to 3 ½ feet. They have a very beautiful tortoiseshell pattern on their carapace that is very sort after. You will mostly find these turtles among the mangrove swamps, reefs. Lagoons, rocky areas, and estuaries in the tropical and subtropical waters of the Atlantic, Pacific, and Indian Oceans.
Their names come from the shape of their beak that is similar to that of a bird that can crack coral reefs to reach sea sponges which are mostly all that these turtles eat. Hawksbills will occasionally eat small amounts of squid, shrimp, sea cucumbers, sea stars, mollusks, crabs, some algae, and sea squirts.
Olive ridley turtle
These are the smallest marine turtles that weigh less than 100 pounds and gets its name from its olive-colored shell. As adults, these turtles live in warm water close to the shore. Olive ridley turtles are mostly found in the tropical parts of the world. Hundreds of females can go ashore to find the right spot to lay their eggs of about 100 eggs in one night. This mostly happens along the Central American and Indian coasts. These turtles mostly eat invertebrates like jellyfish, crabs, sea squirts, rock lobster, and shrimp, but they primarily eat algae.
Kemp’s ridley turtle
This is the most endangered sea turtle and is named after the fisherman who first described them, Richard Kemp. This is the smallest sea turtle that weighs up to 100 pounds and 30 inches long. They hunt their prey in the sandy or muddy bottoms in the temperate and subtropical waters in the Gulf of Mexico and western Atlantic. The females are known for mass nesting on the same beach at Rancho Nuevo in Mexico. These turtles prefer to eat benthic organisms like crabs.
Flatback turtle
This is a medium-sized sea turtle that is only found in the coastal coral reef and grassy shallows in the coastal waters of Australia and the Gulf of Papua New Guinea that is less than 200 feet deep. They weigh about 200 pounds and can grow to a length of about 3 feet. They have a very smooth and waxy shell that can be easily damaged. Flatback turtles got their name from their flattened carapace that is olive-gray and their plastron is pale yellow. The females lay eggs every 2 weeks during the nesting season and come back every 2-3 years to nest. Although the size of their egg clutch is relatively small and they’re medium-sized turtles, they lay large eggs that are almost as big as the eggs for the leatherback turtle which is a much larger turtle species.
These turtles spend most of their time at the ocean soft-bottom surface away from the coral reefs. This turtle species have a slightly serrated lower jaw that will eat a variety of invertebrates including jellyfish, squid, mollusks, seaweed, soft corals, and sea cucumbers.
Why do sea turtles eat plastics?
Unfortunately, sea turtles can also accidentally consume plastics and other marine debris that they will confuse as their food. Research shows that about half of the sea turtles eat plastic waste because most turtles confuse a floating plastic bag for a jellyfish, algae, or other components that form a large part of their diet. Loggerheads eat plastic about 17% of the time they encounter it mistaking it for jellyfish and the green turtles will probably eat plastic almost every time they’re hunting for algae. However, ingesting plastic isn’t what causes problems for these turtles, it’s the marine debris that entangles them which can easily kill them from drowning or being caught by hunters or predators. Plastic accumulation on the turtle’s nesting beaches puts the baby turtles at risk of getting entangled and preventing them from reaching the sea.
Ingesting plastic for turtles can be a death sentence as sharp plastic can tear their internal organs and the bags can lead to blockage in the intestines which will leave the turtle unable to feed leading to starvation and death. However, if the turtles survive eating plastic it makes the turtles have an unnatural buoyancy which will stunt their growth and cause slow reproduction.
Facts about sea turtle diets
- Seagrass is also known as turtle grass because, in areas like the Caribbean, it’s what the green sea turtle exclusively eats.
- Herbivorous sea turtles are very important in helping to maintain healthy coral reefs by eating algae that can overgrow the corals and kill the reefs.
- Sponges use their glass-like spines and toxins as a defense mechanism against their predators, but the hawksbill turtle is immune to it so it doesn’t have to compete to get its food. These turtles don’t eat all types of sponges which allows the rare sponges to grow giving the sponges more diversity.
- Some sea turtles can travel thousands of miles in search of food. For example, the leatherback turtle will travel across the Pacific Ocean from Asia to the west coast of the U.S in search of jellyfish.
- Leatherback turtles are more likely to eat plastic bags because they resemble jellyfish floating in the water. Ingesting plastic will often result kill the turtles.
Interesting things you didn’t know about sea turtles
- Sea turtles are amazing and beautiful creatures that are well adapted to the ocean, but they still need air to survive. Their size will vary depending on the species and they live in different environments that determine their diet.
- Like most turtles, the sex of sea turtles is dependent on the temperatures in the nest. If the temperatures in the sand are cooler, the hatchlings will be males, but if the sand is warmer, the hatchlings will be females. However, if the temperatures fluctuate between the two extremes, the hatchlings will be both male and females.
- As reptiles, sea turtles need air, but under natural conditions, they can stay underwater for a long period and they can even sleep underwater. Sea turtles will spend most of their time at sea but will go ashore to either mate, nest, or back on the beach. They can hold their breath underwater for more than 5 hours by slowing down their heart rate to up to a beat after every nine minutes to help conserve oxygen.
- The green sea turtle’s main diet is more plant-based and they mostly eat seagrass and this keeps the seagrass short and prevents it from becoming tall and becoming harmful to other sea creatures.
- Sea turtles are among the oldest reptiles and sea creatures in the world before the alligators, snakes, and crocodiles. They date back to the age of the dinosaurs about 200 million years ago.
- Just like the bones in your body, the shell of a turtle is actually a part of its skeleton and it’s made up to 50 bones including the turtle’s rib cage and spine.
- Contrary to what people believe, turtles can’t come out of their shells. This means that the turtle can’t grow bigger than its shell.
- Sea turtles don’t have a favorite food and although most of them will eat the jellyfish, each species will eat a variety of food depending on their habitat. Loggerhead turtles prefer to eat crustaceans, leatherbacks prefer eating jellyfish, hawksbills prefer the sea sponges and the green turtles prefer to eat seagrass.
- Female sea turtles can lay between 100-125 eggs per nest and will nest multiple times two weeks apart for several months. The eggs hatch after about 2 months and the tiny turtles will hurry into the open sea. However, only one in a thousand will survive and make it to adulthood.
- Turtles cry, but it’s not because they’re sad. They have glands in their eyes that help to remove excess salt which makes them look like they’re crying, but they’re just doing some cleaning of their body.
- Some sea turtles will travel long distances in search of food while others will remain close to their home. The loggerheads and leatherbacks can migrate over long distances every year looking for food and nesting grounds, while olive ridleys and greens will travel shorter distances and the hawksbills will rarely leave their home.
- Most sea turtles, except the Kemp’s ridley turtle that nests during the day, nest at night and always on the same beach they were born.
Conclusion
Sea turtles are magnificent creatures that have been around for thousands of years that unfortunately face many dangers as they travel the seas including getting entangled in fishing nets, accidental capture, ocean pollution, poaching, and coastal development. Protecting their nesting habitat, reducing marine pollution, reducing your carbon footprint, and watching out for sea turtles when you’re out on a boat can go a long way in improving their odds.