Most animals get by through the world thanks to their different senses, such as the sense of smell, taste, sight, hearing, and touch. Some animals are even well known for a sense or two, like how eagles and birds, in general, are known for their keen sense of sight, or how dogs are known for their keen sense of smell and hearing.
But what about turtles? Sure, they’re known for being slow and for having a tough outer shell that protects them. But what about their senses? And specifically, what about their sight and their hearing?
Well, turtles actually have a very keen sense of sight and can see pretty far. As for their hearing…it’s safe to say that it’s their weakest sense, so they don’t hear things from very far off.
But let’s get into more detail about both their sight and their hearing, and figure out an estimate of how far they can see and hear.
Turtles and Their Sense of Sight
Turtles have a surprisingly very good sense of sight, with their eyes capable of tracking moving prey with ease, even when underwater. Turtles can also very easily maneuver around objects and will see things from decently far away.
Humans can see within a wavelength of between 400 nm and 740 nm. Meanwhile, turtles will see in different wavelengths depending on their species.
They can also see in wavelengths between 400 nm and 740 nm, just like humans. However, as a general rule, turtles seem to see a lot better in shorter wavelengths, between 300 and 370 nm.
This shorter wavelength is within the range of ultraviolet light, so turtles actually have UV light receptors, and as such, they see a lot more colors than we do!
But let’s explain some of the main different aspects of turtle sight:
Turtle Sight and Colors:
In the past, it was thought that turtles couldn’t really see color at all and that their sight was in greyscale. But of course, now we know that they see even more colors than we can name.
Turtles are particularly sensitive when it comes to differentiating between different shades of red, and taking into account how turtles react to different colors…red, orange, and yellow seem to be their favorite! Or at the very least, the ones they see the best.
The red color isn’t just unique to turtles too, according to a study that was published in the Proceedings of the Royal Society B, most reptiles and birds actually see red differently than how we humans do.
They have a gene (CYP2J19) that can be traced all the way back to the dinosaurs, which allows them to see far more shades of red than we can even imagine!
As for yellow and orange, the reason why we say they are the favorite colors of turtles is that they are usually attracted to any object of this color.
Most turtle keepers claim that turtles will move towards red, yellow, and orange things, in order to investigate them. And according to Animal Planet, this is because the turtles want to find out if these red, orange and yellow objects are edible!
Turtle Sight in the Dark:
Turtles aren’t completely blind during the night, and they can see similar to how we humans can when it gets dark. However, they are diurnal animals, and as such, they do not have any night vision, because they’ll just be asleep.
Nevertheless, they can still get by in the dark pretty well, as their eyes will adjust. Just like humans, during the day a turtle’s iris will narrow, and the pupil will constrict, limiting the light the eyes receive.
And at night, the pupils will enlarge to receive more light, so that they can still move about decently well in the dark.
But again, no night vision like the one that cats and owls have, as they lack the tapetum lucidum layer of tissue that would allow for this.
Turtle Sight Underwater:
There are many different types of turtles, and most of them are either aquatic or semi-aquatic, which means they will spend most of their life underwater. These types of turtles will only ever come out to the surface to breathe, sunbathe, lay their eggs, and sometimes sleep.
So as they spend most of their lives underwater, we need to talk about their eyesight in those conditions. Because, unlike humans, turtle eyes are adapted to both the surface and underwater conditions, allowing them to also see when they are in their aquatic habitat.
Humans have a curved cornea that refracts light so that we can see perfectly in the air. But underwater, our cornea cannot refract light, and this is why our vision isn’t great underwater. Fully aquatic animals, like fish, on the other hand, use their lenses to refract light, instead of their cornea.
Turtles need to have the best of both worlds, in order to be able to see both on land and underwater. They do this by having a flat cornea and spherical lenses. The combination of this allows them to see perfectly both in the air and underwater.
Turtles and Their Sense of Hearing:
Turtles don’t have the best sense of hearing, but they still need to be able to hear in order to avoid predators out in the wild and avoid dangers.
The thing is, while humans and most animals have outer ears, turtles simply have thin flaps of skin that cover internal ears. These skin flaps will allow vibrations and low-frequency sound to enter into the ear canal so that they can hear, but they will not be able to hear much.
What turtle ears can do, however, is sense air displacement and detect vibrations from the ground. So even though they can’t hear birds chirping in the trees, they can “hear” when a bird lands nearby on the ground. So we could say that their sense of hearing is very much limited to a small bubble around them.
Underwater, hearing isn’t really that important at all. Instead, their hearing will help them detect low vibrations and changes in water pressure. And this helps them navigate just fine. Plus they have other senses to help them!
How far can turtles see and hear?
Turtles are pretty far-sighted when they are underwater, which is where they will mostly hunt for vision and live, as most turtles are either aquatic or semi-aquatic.
However, when on land, turtles are quite short-sighted, and will not be able to see very far away.
As for hearing, turtles cannot hear very far at all. Instead, they use other senses to navigate and avoid predators.