Owls are one of the most popular nocturnal animals. Not only is it a raptor and bird of prey, it is designed in a way that has made it a mystery to humans over the centuries.
Owls have large eyes which let in more light and they have an abundance of rods in their eyes which help them see better at night.
If you have been curious about how owls see at night then this article is about to satisfy your curiosity.
We will discuss how owls see at night, if they can see in total darkness, what colors they see among other things.
Do Owls See At Night? How?
Owls see well at night, they are nocturnal birds of prey and their night vision is superb. Owls majorly eat rodents including rats and mice.
Owls’ eyes have adaptations which help them to have superior night vision. One of these is their eye size.
Owls have very large eyes in comparison to their bodies. You see owls with round eyes which stare eerily at you..
These large eyes let in more light than smaller ones and they also expand a lot at night to help them see more.
Another structure that helps owls see better than humans are the rods within the eyes.
In human eyes we have structures called cones and rods. Cones are more adapted for seeing colors while the rods help to focus lights within the eyes.
Owls have a greater number of rods and fewer cones, this means that owls can see a lot much more than humans at night because the rods help them focus the light.
The last adaptation which helps owls see better at night is the tapetum lucidum.
This is a mirror-like tissue behind the owl’s retina which reflects light on the rods. When light moves past the rods and touches the mirror, it reflects the light back to the rods.
This helps the owl to catch light twice, in essence it increases the light available to the photoreceptors and gives the owl superior vision.
Related: Here is an article I wrote on why owls blink one eye at a time
Can Owls See In Total Darkness?
Owls cannot see in total darkness and this because of the structure of the eye.
In every animal’s eyes, light usually enters the eye before an image is created and then sent to the brain for interpretation.
It is necessary for some light now matter how small to be available for the eye to see.
No animal can see in total darkness. For the owl that hunts in darkness however, their eyes are more suited to dim light.
Due to the abundance of rods in the retinas and the tapetum lucidum, owls are able to have a superior vision.
Very important to know also is the fact that owls have a well developed auditory system which aids in hunting prey.
Owls are known to have crooked asymmetrical ears which registers sounds at different intervals and help the owl easily pinpoint the source of the prey.
When in total darkness, the owl relies on its crooked ears to pick out the exact location of a prey.
The sound of the rodent usually reaches one ear a second before it reaches the other.
In between that period, the owl calculates the exact distance from the rodent and when it hears the sound in both ears it will swoop down and attack
Of course because owls can’t see in pitch darkness, if it miscalculates it will end up missing the prey and crash landing.
How Does An Owl Look At Night?
If you have ever seen an owl at night and pointed a flashlight at it, you would see it’s eyes glowing and reflecting the light back at you.
Owls are active at night and they are usually seen perched on trees or other places.
With their large eyes and head, flat faces and small break which is down turned, owls can be pretty eerie when seen at night.
Owls have a rigid posture and can actually turn their heads 270 degrees, which means they can face forward and turn their heads almost to the back.
With their glowing eyes and human-like voices, it is little wonder the owl is one bird that has been rich in mystery and folklore over the centuries.
Also check out this article on why owls sleep during the day
What Colors Do Owls See?
Owls like all other birds are tetrachromats i.e. they see four colors namely blue, green, red and UV. Humans only see three colors omitting the UV.
In essence, owls have a lot more photoreceptor rods in their retina than cones. Cones are for seeing and detecting colors and work better in bright light.
Rods however work well in dim light and help the owls let in more light.
As a result of this the owls lose color vision and see a lot better at night. This means their vision during the day is blurry.
So in essence they see the world in faded quality and see muted rays of the colors we see.
Some scientists even believe owls are color blind and only see white, black and grey
Can Owls See Clearly At Night?
Owls can see more clearly at night than in the day and they can definitely see about 75 to 100 times better than humans at night.
During the day, owls prefer to sleep or if they do not, they will shut out their eyes against the light as it is too bright for their eyes.
Due to the presence of more rods than cones (about 10,000 rods per sq mm) in the owls’ retinas they are able to see more clearly in dim light and as such stalk their prey and navigate in the dark.
Asides that, the owl’s eyes are larger and the pupils can dilate to take in even the smallest amount of light.
Also the distance between the owl’s eyes lens and the retina is greater than that observed in humans.
As a result of this, the image formed on the owl’s retina is bigger than that of a human.
Can Owls See In The Day
Contrary to the opinion that owls are blind during the day, owls can see quite well during the day.
They can adjust their irises to reduce the amount of light that comes into their eye at night.
To block out the bright light, they usually close their eyes halfway and this might make them appear sleepy. In actual fact, they are awake and very much alert.
Owls are sometimes seen being active during the day and as such they can pretty much move around when they choose to.
They can also see the ground quite well especially when they are eyes are half way closed with their upper eyelids.
Do Owls’ Eyes Glow In The Dark?
Yes owls’ eyes do glow in the dark, and can reflect different colours depending on their species.
This phenomenon of eyes glowing in the dark is called eyeshine.
Owls are not the only animals that have eyeshine, most nocturnal animals like cats also do.
This eyeshine is caused by the animal’s tapetum lucidum.
The tapetum lucidum is a membrane at the back of the eye which usually acts as a retroreflector.
This means when you point a flashlight at the owl’s eyes, the tapetum lucidum reflects the light back to the source (flashlight) causing the glow.
The Colour of the owl eyeshine differs from species to species for example, the flammulated owl reflects white colour, the great horned owl reflects yellow and the screech, barn and barred owls reflect red eyeshine.
Can Owls Move Their Eyes
Owls cannot move their eyes and this is another interesting feature they possess. Owls cannot move their eyes because they do not have eyeballs.
Their eyes instead have a tube-like shape which is held fast in place by a set of bones called sclerotic rings.
This is quite different to humans who have spherical eyes and do not need the sclerotic rings and can move them around.
To make up for this, owls are able to twist their necks about 270° in both directions and 90° up and down.
Conclusion
Owls are quite interesting creatures of the night. They are great hunters and are known for their wide eyed stares.
Owls are better adapted to seeing in the dark than humans because they have larger eyes.
They also have a greater presence of photoreceptor rods in their retina which help them see better in dim light.
As a result, owls have a muted view of the world as they possess less cones for color detection.
They also exhibit eyeshine which is caused by the tapetum lucidum reflecting light back to the source and making their eyes glow.
