The Big-eyed Owls are an intelligent and intriguing avian species that attract birders’ attention and curiosity with their nocturnal existence and behavior.
From Halloween festivals to horror films, owls have been considered symbols of the occult and mythology for years.
Owls are associated with evil omens, witchcraft, and shamans in many human clusters because of their ominous hooting sounds, haunting calls, secretive habits, and good eyesight at night.
A species’ eyes and eyeballs, sockets, and structural aspects play an essential role in survival and hunting.
Humans have incredible eyesight to see a wide range of colors and view objects clearly for miles if it’s not obstructed. However, owls are nocturnal (active at night) and farsighted.
Therefore, they cannot focus or view objects even a few centimeters away from them.
Do you think owls have eyeballs? Can owls see colors? Read on below to know about owls’ eyesight.
Do owls have eyes? Do they have good vision?
Yes, owls have large tube-shaped eyes. Like humans, owls have terrific binocular vision. However, owls’ have forward-facing eyes and have a more excellent range of binocular vision than animals having eyes on their head.
Owls’ eyes occupy 3% of their whole body weight. Their eyes are farsighted. The sensitive whisker-like hair covering the base of their beak helps detect close objects and makes their appearance more like humans than avian species.
Like humans, owls don’t shrink their pupils in the bright daylight. Instead, they often close their eyes halfway and look half asleep or even sleepy to block shiny light.
The retina of both birds and humans has a particular area called the fovea, where rods and cones(vision cells) are concentrated. Their eyes have more rods than human eyes, making them sensitive to light.
In owls, the fovea is found in the upper part of the retina, so they get a clear view of objects below and helps to catch prey on the ground.
During daylight, owls can close their eyes halfway to block bright light, but still, they will get a clear and perfect view of the ground.
Do owls have eyeballs?
Owls don’t have eyeballs and can’t move or roll their eyes within sockets like human eyes to view objects around them. Instead, they have to either move or swivel their neck to see the things around them.
Their tube-shaped and elongated eyes are immobile, held in a static place in the skull by a bony structure called sclerotic rings.
To change views or expand their field of view, the owls frequently “bob and weave” or turn their entire head. They rotate their neck up to 270° in left and right and move 90° up-and-down to look around them without turning their shoulders.
When they swivel their neck at 270° and cut off blood circulation, a blood-pooling system helps store blood to give their brain and eyes power.
What is unique about an owl’s eyes?
The owls’ eyes are nocturnal – which means they can be active at night, have excellent binocular vision, and their third eyelid (nictitating membrane) keeps their tube eyes clean, making the owls’ eyes stand out among the other avian species’ eyesight.
Like humans, owls’ eyes can focus the prey with both eyes simultaneously and boost depth perception.
In addition, the face-forwarding owl’s eyes have better and greater range binocular eyesight than other animals having eyes on the head. This vision helps them to judge the weight, height, and distance of an object.
For instance, an owl’s field of view is about 110°, and 64% of their eyesight range is from binocular vision.
Owls’ eyes have three more prominent eyelids, lower eyelids, and the third eyelid called the nictitating membrane.
The upper eyelid is larger than the lower eyelid. Therefore, it closes down when it blinks. The lower eyelid covers the eyes when they sleep.
The translucent nictitating membrane moves horizontally from the inner corner to the outer corner of the owl’s eyes.
The owls use the third eyelid to get a clear view of the prey while hunting. Meanwhile, this membrane protects their eyes from damage and injury.
Related Read: How To Comfort A Dying Owl?
Can owls see at night? Can they see in total darkness?
Yes, owls have good eyesight at night because of densely packed rods in their retina and the mirror-like structure at the back of their eyes.
Densely packed rods
All species have photoreceptors like cones and rod shapes in their retina. The retinal cones are responsible for color vision and bright light, and the rods are sensitive to light and accountable for dim lights.
They get superior night vision and lose color vision due to the domination of rods in the vision cells.
Mirror at the back of their eyes
Owls have a mirror at the back of their eye layer or “eyeshine,” known as tapetum lucidum. When sunlight passes through the rods and hits rods and reflects the visible light to the rods, the owls have two chances to capture the lights.
This reflection lights increases the light visibility to the photoreceptors in the retina and gives it during the night for better eyesight.
Owls can see only limited colors or in monochrome because of fewer cones in the vision cells. In the darkness, owls use their ears to hunt down their hidden prey.
At night, owls’ eyes seem to glow brightly due to the tapetum lucidum layer.
Vision plays a vital role in the survival of every living organism. There are quite a few species with no eyes, tiny eyes, with no eyeballs, etc., Yet, they survive with whatever features they have. The Owls are a classic example.