Why Is My Turtle Biting His Arm? Causes, Meanings, and How to Stop It

Have you ever seen your turtle bite his own arm? I know it can be scary when you first see it. You might think your turtle is sick or hurt. I felt the same way when I first saw my turtle doing this strange thing!

When your turtle bites his arm, it usually means he is shedding his skin. The old skin gets itchy and loose. Your turtle uses his mouth to pull off the old skin. Sometimes the water in his tank is dirty and makes his skin feel bad. Other times, something might be stuck under his scales and he wants to get it out.

In this guide, I will tell you everything about why turtles bite their arms. I will also show you how to help your turtle and when you should worry.

Why Is My Turtle Biting His Arm?

I want you to know that this is normal turtle behavior. Many turtle owners see this happen. I have seen it many times with my own turtles. At first, I was worried too. But then I learned it is usually not a big problem.

Let me tell you all the reasons why your turtle might bite his arm.

Your Turtle Is Shedding His Skin

This is the number one reason! Just like snakes, turtles shed their skin too. When the old skin starts to come off, it feels very itchy. Your turtle will bite his arm to help pull off the loose skin pieces.

I have watched my turtle do this during shedding time. The skin on his arms gets loose and starts to peel. He uses his mouth to grab the loose pieces and pull them off. It helps him shed faster and feel better.

Shedding is a good thing. It means your turtle is growing and healthy. Young turtles shed more often than old turtles because they grow faster.

His Skin Feels Itchy or Irritated

Sometimes your turtle’s skin can feel irritated. This makes him want to scratch or bite the itchy spot. But turtles can’t scratch with their hands like we do. So they use their mouth instead.

The water in your turtle’s tank can make his skin irritated. If you don’t change the water often, bad chemicals build up in it. Ammonia and nitrites are chemicals that come from turtle poop and old food. These chemicals make the water dirty and hurt your turtle’s skin.

Dirty water makes your turtle’s skin feel itchy and uncomfortable. Your turtle will bite his arms to try to make the itching stop.

Mites Are Attacking Your Turtle

Mites are tiny bugs that can live on your turtle’s body. They are so small you might not see them at first. These little bugs bite your turtle’s skin and make him very itchy.

If mites are the problem, your turtle will bite his arms a lot. He is trying to get the mites off his body. Look very closely at your turtle’s skin. You might see tiny red or black dots moving around. Those are mites!

Fungus can also grow on your turtle’s skin. Fungus looks like white or gray fuzzy spots. It makes your turtle’s skin feel bad too. Your turtle will bite at the fungus spots to try to remove them.

Something Is Stuck Under His Scales

Sometimes small things can get stuck under your turtle’s scales. It could be a piece of gravel, sand, or even a tiny plant piece. When something is stuck under his scales, it feels very uncomfortable.

Your turtle will bite at his arm to try to pull out whatever is stuck. I once found a small piece of wood stuck under my turtle’s scale. After I carefully removed it with tweezers, he stopped biting that spot.

He Doesn’t Have Good UV Lights

Turtles need special UV lights in their tank. These lights give them UVA and UVB rays. These rays help your turtle stay healthy and strong.

Without good UV lights, your turtle can get skin problems. His skin might develop rashes or dry patches. These rashes are itchy and painful. Your turtle will bite his arms to try to make the rashes go away.

UV lights also help your turtle make vitamin D in his body. Without vitamin D, his bones and shell get weak. His skin can also become unhealthy.

Your Turtle Is Bored or Stressed

Turtles need things to do in their tank. If your turtle lives in a boring tank with nothing to explore, he will get bored. When turtles get bored, they sometimes do strange things.

A small tank can also make your turtle feel trapped and stressed. Imagine living in a tiny room all day with nothing to do. You would feel bad too! Your turtle might start biting his arms because he is frustrated.

Stress can come from many things. Maybe your turtle doesn’t have enough space to swim. Maybe there are no places for him to hide. Maybe the tank is too noisy or in a busy place. All these things can stress your turtle out.

He Is Hungry

Sometimes a very hungry turtle will bite his arms. This doesn’t happen often, but it can happen if you forget to feed your turtle or don’t feed him enough food.

A hungry turtle might also try to eat his own shed skin or even eat gravel from the bottom of the tank. This is not good! Make sure you feed your turtle every day if he is young, or every other day if he is grown up.

How Do I Stop My Turtle From Biting His Arm?

Now that you know why your turtle bites his arm, I will tell you how to help him stop. The solution depends on what is causing the problem.

Let me share all the ways I help my turtles.

Make Sure Your Turtle’s Home Is Comfortable

Your turtle needs a good home to be happy. Here’s what I do for my turtles:

Give him a big tank. A bigger tank is always better. Your turtle needs room to swim around and explore. For most turtles, I recommend at least a 40-gallon tank. Bigger turtles need even bigger tanks.

Add fun things to the tank. Put plants, rocks, and hiding spots in your turtle’s tank. You can use fake plants or real ones. Add some decorations that your turtle can swim around and explore. This keeps him busy and happy.

Keep the water temperature right. The water should be between 75 and 80 degrees. The basking spot should be between 85 and 95 degrees. Use a water heater and a basking lamp to keep the temperatures perfect.

Get your turtle some friends. If your tank is big enough, you can add another turtle or some fish. Make sure the fish are big enough that your turtle won’t eat them! Having friends in the tank makes your turtle less bored.

Put the tank in a quiet place. Don’t put your turtle’s tank in a noisy room or where people walk by all the time. Turtles like peace and quiet.

Keep Your Turtle’s Tank Very Clean

Clean water is so important for your turtle’s health. Dirty water is one of the main reasons turtles get itchy skin and bite their arms.

Here’s my cleaning routine:

Change some water every week. Take out about 25% of the water and add fresh new water. This keeps the chemicals from building up too much.

Use a good filter. A filter cleans the water all day long. Get a filter that is strong enough for your tank size. I like to get a filter that is made for a tank bigger than mine. This makes sure it works really well.

Clean the tank decorations. Once a month, take out the rocks, plants, and decorations. Scrub them with warm water to remove algae and dirt. Don’t use soap because soap can hurt your turtle!

Test the water. Buy a water testing kit from the pet store. Test your water once a week to make sure the ammonia, nitrites, and nitrates are at safe levels.

Remove old food. If your turtle doesn’t eat all his food, take out the leftover pieces after 15 minutes. Old food makes the water dirty very fast.

Feed Your Turtle The Right Food

Good food keeps your turtle healthy and happy. When your turtle eats the right foods, his skin stays healthy and he doesn’t get itchy.

Here’s what I feed my turtles:

Turtle pellets. These are the main food for most pet turtles. Buy good quality pellets from the pet store. Follow the directions on the package for how much to feed.

Fresh vegetables. Give your turtle leafy greens like lettuce, kale, and collard greens. You can also give small pieces of carrots and squash.

Protein foods. Feed your turtle small pieces of fish, shrimp, or worms. Don’t give these every day. A few times a week is enough.

Calcium. Your turtle needs calcium for his shell and bones. You can buy calcium powder and sprinkle it on his food. Or give him a cuttlebone to nibble on.

Feed on a schedule. Young turtles need food every day. Adult turtles can eat every other day. Stick to a schedule so your turtle knows when to expect food.

Check For Mites and Remove Them

If you see mites on your turtle, you need to get rid of them right away. Here’s what I do:

Give your turtle a bath. Put your turtle in a container with warm water. Gently scrub his skin with a soft toothbrush. This can remove some of the mites.

Clean the entire tank. Take everything out of the tank. Wash it all with hot water. Let everything dry completely before putting it back.

Use mite medicine. Take your turtle to the vet. The vet can give you special medicine to kill the mites. Follow the vet’s directions carefully.

Keep checking your turtle. After treatment, check your turtle every day to make sure the mites don’t come back.

Make Sure The UV Lights Are Working

UV lights don’t last forever. Even if the light still turns on, it might not be making the UV rays your turtle needs anymore.

Replace UV bulbs every 6 months. Mark your calendar so you remember when to change the bulb. Some bulbs last 12 months, but most need changing every 6 months.

Keep the light close enough. The UV light should be about 10 to 12 inches above your turtle’s basking spot. If it’s too far away, your turtle won’t get enough UV rays.

Let your turtle bask. Make sure your turtle has a dry spot where he can climb out of the water. He should spend several hours a day under the UV light.

Remove Stuck Objects Carefully

If you find something stuck under your turtle’s scales, you need to remove it very gently.

Use tweezers. Get a pair of clean tweezers. Carefully grab the stuck object and pull it out slowly. Be very gentle so you don’t hurt your turtle’s skin.

Ask for help if needed. If the object is stuck really deep or you’re worried about hurting your turtle, take him to the vet. The vet has special tools and can remove it safely.

Help Your Turtle During Shedding

If your turtle is shedding, you can help make it easier for him.

Give him a deeper water area. Turtles shed better when they can soak in deep water. Make sure your turtle has a place to swim and soak.

Keep humidity good. The air around the tank should not be too dry. You can use a humidifier in the room if the air is very dry.

Don’t pull the skin. Never try to pull off your turtle’s shedding skin yourself. Let your turtle do it naturally. Pulling the skin can hurt him.

Wait it out. Shedding is normal and natural. As long as your turtle is eating well and seems healthy, just let him shed in his own time.

When Should I Worry?

Most of the time, arm biting is not a serious problem. But sometimes you should take your turtle to the vet.

Take your turtle to the vet if:

He bites his arm all the time. If your turtle never stops biting his arm, something might be seriously wrong.

You see blood. If your turtle bites himself so hard that he bleeds, you need to see a vet right away.

His skin looks infected. Red, swollen, or oozing skin means infection. The vet needs to give your turtle medicine.

He stops eating. If your turtle won’t eat and is also biting his arm, he might be very sick.

He seems weak. If your turtle is swimming funny, not moving much, or acting strange, go to the vet.

The skin won’t shed. If your turtle has been trying to shed the same piece of skin for many weeks, the vet can help.

You see lots of mites. A bad mite infestation needs vet treatment.

My Final Thoughts

I want you to know that turtles biting their arms is usually normal behavior. I have seen my turtles do this many times over the years. Most of the time, they are just shedding their skin or feeling a little itchy.

The most common reason is shedding. The old skin gets itchy and loose. Your turtle uses his mouth to help pull off the loose skin pieces. This is completely normal and nothing to worry about.

But sometimes arm biting means there is a problem. Dirty water can irritate your turtle’s skin. Mites and fungus can make him very itchy. A boring tank can make him stressed. Not having good food or UV lights can cause skin problems too.

The good news is that you can help your turtle! Give him a big clean tank with lots of things to explore. Change his water every week and use a good filter. Feed him healthy foods every day. Make sure his UV lights are working. Keep the temperature perfect. Do all these things and your turtle will be much happier.

If you do everything right but your turtle still keeps biting his arm a lot, then go see a reptile vet. The vet can check if there is a medical problem and give your turtle medicine if he needs it.

I hope this guide helped you understand your turtle better. Remember, you are a good turtle owner because you care enough to ask questions and learn. Your turtle is lucky to have you taking care of him!