What is your turtle's shell telling you?

Your turtle's shell may seem like a lifeless container the reptile simply lives in. But the truth is your turtle's shell is actually part of its skeleton and a major structure of its anatomy. The surface of your turtle's shell is made of keratin, the same protein that makes up fingernails, horns, or claws, but underneath are living tissues and the bones of your turtle's backbone structure. Your turtle's shell can be a source of information about various aspects of its health and can even give you clues about the turtle's age.

What's your turtle's shell telling you...

€¦about your turtle's age?

Let's start with a fun one. You can use markings on your turtle's shell to form an estimate of the pet's age. This technique may not be super accurate, so take your findings as a general estimate at best.

To estimate your pet's age, you need to examine one of the scutes on your turtle's shell. Scutes are the geometrical shapes you see on your turtle's back. Within the scute (and depending on the turtle), you may be able to see faint layers or rings, somewhat similar to tree rings.

According to one theory, these rings form twice a year, so if you count the rings in one scute and divide that number in half, you have a (very) rough estimate of age. This equation is not precise because the rings form in response to the turtle's nutrition and growth, so they may grow more or fewer rings than two a year. But it's a fun way to get an estimate if you don't know your turtle's exact age.

If your turtle is fairly young, you can also measure the length of the carapace — the shell's "top" — and compare it to the length of an adult of the same species (maybe one that you know how old it is) to get a ballpark age. This is probably more reliable than the other method, though it's only useful in young turtles under age 5.

€¦about your turtle's growth?

Some species of aquatic turtles routinely "shed" sections of their scutes as they grow, which can help keep the shell fresh, healthy, and lightweight. When this happens, you may see small pieces of scutes flaking off, but it shouldn't appear particularly dramatic. The shell will regrow the missing pieces one by one, resulting in a larger shell that fits your turtle as they mature. This type of shedding is a normal and natural part of turtle growth in certain aquatic species, so it isn't a cause for alarm.

...about its habitat cleanliness?

You might notice your turtle's shell collecting a layer of algae. While a small amount isn't a huge concern — light algae on the shell is easily removed with a toothbrush and gentle brushing — this may be an indication that you need to address habitat hygiene. You might want to use a turtle-safe glass cleaner, as well as something for the water. A product that supplies beneficial bacteria to the habitat can also help keep things clean.

€¦about your turtle's health?

Your turtle's shell can give you a pretty good indication of several health concerns. Routinely examine the shell, top and bottom, looking for any weak or soft spots on the shell. The shell should normally be fairly hard and smooth. If there are soft spots or significant flaking, it's time to take your turtle to your veterinarian for a checkup.

Additionally, irregular shell growth, sometimes called "pyramiding," can indicate a tortoise's diet was insufficient at some time in the past. It could also indicate disease. These are issues that a reptile-specialist veterinarian can provide advice on.

Your turtle or tortoise's shell can also be damaged from injury, so be sure to include only safe décor in the habitat — nothing too sharp or abrasive.

The Bottom Line on Your Turtle's Shell

Your turtle's shell seems tough — and it is — but it's also hiding living tissue just under the surface, so it's much more than simple protection for the animal. Keeping a close watch on the appearance of the shell is important to help you recognize certain issues before they develop into bigger problems and to keep your turtle happy and healthy!