Can Turtles See In The Dark?

Sea turtles are common spicies, you may have seen them crawling around in the dark, so you may ask,

can sea turtles see in the dark?

Yes, sea turtles can see in the dark. They don't have night vision to see clearly in the dark, but once their

eyes adjust in the dark, they see things more in red coloured shadows because they have Tapetum

lucidum in their eyes which is known as the redness gene.

Let's now understand how turtles can see in the dark if they have better vision than humans.

 

How do turtles see in the dark?

Tortoise vision is similar to human vision with a few differences. 

in the dark, things appear more reddish in colour to turtles than to humans. 

Let's understand how tortoise vision works with an example.  

In total darkness we humans cannot see things around instantly.

 It is only after some time when our eyes adjust in the dark, that we see things around us.

 

However, things are not as clear as in broad daylight. 

A turtle's vision is the same as that of a human. In the dark, turtles cannot see right away.

But after a while, once the turtle's iris adjusts and allows more light into the eye, the turtle can see in the

dark.

It will not be able to see clearly 

That's also the reason why sometimes you find your pet turtle wandering around the tank.

Okay! Now that we know that turtles can see in the dark, let's find out if turtles have night vision like birds

or nocturnal animals.

How can we verify that turtles don't have night vision?

If you have a pet tortoise, you may sometimes see it wandering around outside at night. 

This allows you to ask if the turtle has night vision. Tortoises do not have night vision like owls.

Tortoise eyes are not much different from humans. 

Before we talk further about night vision

 

Night vision refers to the ability of the eye to see things clearly in dim light.

Most nocturnal animals have night vision because they have tapetum lucidum in their eyes. 

Tapedum Lucidum refers to a layer of tissue in the eye located just behind the retina. It acts as a

retroreflector.

It increases visual sensitivity in low light conditions.

It refers to the membrane in the eye that sends back photons in the eye, thus allowing nocturnal animals

to see clearly in the dark.

Now, to determine if a turtle has night vision, you just need to photograph its eyes in the dark using your

mobile phone flash.

Animals that have night vision will have light in their eyes, and it will reflect in the photo.

In contrast, a tortoise's eyes do not glow. This is a clear indication that turtles do not have night vision. 

 

Can turtles see underwater?

It is difficult for humans to see long distances underwater. But the same is not true for turtles.

Turtles can see underwater as clearly as they can on land.

So, what sets turtles apart? How is it that they can see things better underwater than humans?

Even so, Turtles can see better underwater because they live in water, and their eyes have adapted to

see underwater.

Underwater, tortoise eyes produce mucus.

This mucus forms a protective layer on their eyes and keeps their vision from being impaired by water

salts and bacteria. 

Mucus looks more like tears, and you might think it's a tortoise crying. Mucus is not tears 

Mucus helps remove excess salt from the tortoise's body through their eyes. 

The only barrier to clear vision underwater is dirt. If the water is polluted, the turtle cannot see clearly.

However, this rarely happens in the wild as the water is usually clean. 

But in captivity, if the aquarium water is contaminated, it will affect the turtle's vision.

Your tortoise will not be able to see clearly

 

Point to remember

Turtles can see in the dark after adjusting their eyes to the darkness around them. 

They have more receptors in their eyes than humans. But they don't have night vision

Turtles can even see underwater without much difficulty. 

The only barrier to their vision in water is dirt or bacteria. Turtles struggle to see in polluted water.

Turtles see more things in shades of red than humans because they have the reddish gene.