Different species of sea turtles roam around most of the world’s oceans. Most of these sea turtles are omnivores. Hence, they feed on various living organisms and plants under the sea. Like sea turtles, jellyfish also live under the ocean. So, do sea turtles eat jellyfish?
Most sea turtles eat jellyfish. Jellyfish are slow and often roam around in groups, making them easy to catch. Also, sea turtles have developed some physical advantages that enable them to eat jellyfish without any problem.
But do all sea turtles eat jellyfish? And jellyfish have venomous tentacles that they use to sting their attackers. So, how can sea turtles eat them? You will have all your questions answered in this article.
Do All Sea Turtles Eat Jellyfish?
There are seven species of sea turtles. Most of them are omnivores, eating various plants and animals. All sea turtles eat jellyfish at some point in their life.
Green Sea turtles are omnivores during their early age but become herbivores when they reach adulthood. It means adult green turtles do not eat jellyfish. Similarly, young Loggerheads are omnivores, but adults become carnivores. However, adult Loggerheads have been seen eating jellyfish.
On the other hand, leatherbacks are gelatinivores as their primary food source is gelatinous prey like jellyfish, sea squirts, and tunicates. They are the biggest predators of jellyfish. These large size turtles can easily squash jellyfish with their formidable jaws.
Kemp’s ridley turtles are carnivores all their life. Their favorite foods are fish, crabs, shrimp, mollusks, and jellyfish. Next, we have Oliver ridleys. They are omnivores feeding on varieties of plants and animals of the sea. They enjoy hunting and eating crabs, lobsters, shrimps, jellyfish, algae, urchins, and fish.
Like Oliver ridleys, flatbacks are omnivores. They eat sea cucumbers, jellyfish, crabs, shrimps, fish, and seaweed. Then there are hawksbills, often called spongivorous because they mostly eat sponges. But they also eat animals and plants when they do not find their primary food choice. So, they do not mind eating jellyfish.
As you can see, no matter the food preference of different species, all sea turtles prefer eating jellyfish. However, the leatherbacks are the only species that consume jellyfish as their primary food source.
How Do Sea Turtles Eat Jellyfish Without Getting Stung?
You must have been warned about getting stung by jellyfish at the sea beach. Jellyfish may look harmless, but they can inject venom with their tentacles. Jellyfish stings can cause excruciating pain and can leave marks on the skin. It can also cause serious illnesses that can lead to life-threatening conditions.
So, how can sea turtles not get stung by jellyfish and not be affected by venom? Well, unlike humans, sea turtles are not vulnerable to jellyfish stings. Sea turtles have adopted some defensive traits that protect them from jellyfish.
These physical traits are:
- Thick skin
- Powerful beak
- Papillae (covering their throats)
- Blind hunting
Sea turtles have hard shells that protect them from external danger. Most of the body of a turtle is covered by its shell. Yes, the shells of a turtle have some nerves, but a jellyfish cannot inflict much pain by stinging the shell of sea turtles.
Sea turtles are reptiles. They have incredibly thick skin. So, the thick skin protects the parts that a shell does not cover. Even if the jellyfish sting a sea turtle, it cannot penetrate the scaly skin of the turtle.
Sea turtles do not have teeth. Instead, they have sharp beaks with a robust set of jaws. Also, remember the thick skin covering the body? These thick skins also cover the beaks of the sea turtles protecting their mouth from jellyfish venom.
With their powerful beak, sea turtles can easily tear apart the hardest things under the sea. So, they have no problem eating jellyfish. Large-size sea turtles can even separate the venomous tentacles from the body of a jellyfish in one bite.
Papillae Covering Their Throats
Alright, thick skin and the shell protect the turtle from external harm from the jellyfish. But what happens when the turtle swallows the jellyfish? Why doesn’t the jellyfish venom affect the turtle?
Sea turtles have adopted another trait that prevents jellyfish from harming them. They have papillae starting from the esophagus inwards towards their stomach. The papillae are keratinized projections that protect the throat of sea turtles from jellyfish’s venom.
Even if a jellyfish is swallowed alive by a sea turtle, it will be crushed by the papillae inside the turtle’s throat and stomach. This physical trait gives sea turtles the confidence to hunt and eat jellyfish as much as they can find.
The weakest part of a sea turtle is its eyes. It can be very painful if a jellyfish stings them in their eyes. Even the turtles know that. So, when they get too close to jellyfish while attacking, they close their eyes to protect them from the tentacles of the jellyfish.
Sea turtles have learned to hunt, keeping their eye shut. Interestingly, turtles do not have eyelids like humans. But that’s not a problem for them. The thick skin around the eyes closes in and protects the turtle from getting stung by jellyfish.
How Do Sea Turtles Hunt & Eat Jellyfish?
Today, I will talk about how leatherbacks hunt for jellyfish. Leatherbacks are the largest sea turtles. As you know, their main food is jellyfish. Jellyfish are 95% water. Yet, leatherbacks can reach 640 kilograms in weight by eating jellyfish.
The favorite jellyfish for leatherbacks are moon jellies and lion’s mane. Leatherbacks dive deep under the ocean to feed on these jellyfish. There, they find plenty of jellyfish to eat.
The turtles get close to the jellyfish to bite them. The jellyfish are slow, and sea turtles are fast in the water. Thus, the jellies cannot get away from their predators. If the jellyfish is small, sea turtles can consume them whole. But the large jellyfish have to be torn apart to be consumed.
Leatherbacks can eat up to 16,000 calories daily, which is about 73% of their body weight. They fill most of these daily calories by eating jellyfish.
Why Do Sea Turtles Eat Jellyfish?
There are some valid reasons why jellyfish are ideal food for sea turtles.
First, jellyfish are high in nutrient value for leatherbacks. They contain protein which is crucial for a sea turtle’s growth. Protein also helps to repair damaged tissues. Jellyfish contain essential fats necessary for properly functioning the turtle’s cell membranes. It also helps in producing hormones and enzymes in a turtle’s body.
Secondly, it is very easy to hunt jellyfish as they are very slow. They cannot escape from the turtles. Thus, the turtles do not have to put much effort into hunting them. It takes only a few minutes to catch and eat a jellyfish.
Besides, jellyfish are often found roaming in hundreds or thousands. So, sea turtles, like the leatherbacks, do not have to search for other food. They fulfill their daily calorie needs by eating jellyfish swimming in groups.
In summer, leatherbacks consume hundreds of jellyfish to get calories. They use the energy to travel a 9,000km trip to the Indo-Pacific, searching for a partner for breading and finding the right spot for nesting.
Can Sea Turtles Get High Eating Jellyfish?
There is a rumor that sea turtles get high after eating jellyfish. No, sea turtles do not get high after eating jellyfish. This is just a rumor that spread thanks to a certain Disney movie.
Many researchers have talked about the matter, and they agree that the chemical build of jellyfish is not capable of getting sea turtles high. Sea turtles, especially leatherbacks, eat plenty of jellyfish but not to get high. They eat jellyfish because it is easy prey with great nutrient value.
How Sea Turtles Help by Eating Jellyfish?
Without sea turtles, the number of jellyfish in the oceans would be out of control. Some species of jellyfish can produce 45,000 eggs in one night! So, imagine what can happen if these venomous creatures’ population explodes in the oceans! They are dangerous not just for humans but also for other living beings in the sea.
So, it is crucial to protect sea turtles to control the number of jellyfish in the sea. Without leatherbacks in the ocean, jellyfish can take over the ocean, killing the larva and small fishes. Consequently, other sea animals will also perish due to a lack of food.
Unfortunately, humans are unaware of the importance of sea turtles in the ocean. Wastes like plastic bags are often thrown into the sea. Sea turtles often mistake clear plastic bags for jellyfish and eat them. These plastic bags cause intestinal blockages that make the turtles unable to eat, eventually leading to death. Consumption of plastic bags can also hamper the growth and reproduction ability of sea turtles.
Before You Go
Jellyfish are just one kind of food that sea turtles prefer eating. You can learn more about sea turtles and their eating habits from my other articles here: