Thayerbirding is supported by its audience. When you buy through our links, we may earn an affiliate commission. Learn more

Why Can’t Birds See Glass? Discover 6 Reasons Why

Written by Clinton Atkins / Fact Checked by George Dukes

why can't birds see glass

Why can’t birds see glass? This is because they are unaware of glass in their natural environment, and they are not given a chance to perceive it as a barrier. Seeing birds behind glasses a few feet away while in flight, you can expect them to smash into the window. This is a pitying sight that many homeowners don’t want to witness. Understanding this occurrence will shed light on questions and lead to possible solutions.

Reasons Why Birds Can’t See Glass

Birds can’t see glass storks, eagles, and owls. We have learned that the main reason is that glass is not present in its natural habitat and doesn’t have an opportunity to learn about them. To have a deeper understanding of the reason behind the many birds flying into glass accidents, read on.

1. They see color more profoundly

Birds have larger eyes than mammals, which means they have a better vision, which is vital to avoiding collisions and capturing their prey. They also see color more intensely, fuller, and rich than any human eye. When they pick up colors from a reflection, they easily believe it is the real thing.

2. They have poor depth perception

Having depth perception means one can see the world in three dimensions. It is the ability to tell the distance and size of objects. Birds’ eyes on both sides of their head give them a wider field of vision, but it sacrifices their depth perception, which comes from having two eyes facing in the same direction. This means birds see through glass with difficulty.

3. They don’t know how to look for glass windows

Birds don’t learn the same visual cues as humans. These cues help us learn several ways to detect glass. It could be mullions or small cracks that will hint that what we are looking at is glass. But for avians, they see whatever is reflected on the mirror-like surface. They are proven to have good color vision, so birds see color glass. In some cases, humans can also think the reflection they see is reality.

4. They panic when flying into glass


There are instances when birds run into windows while in a panicked state. Like humans, birds also lose focus when panicking. This often happens when they fly away from threats and any loud noise. If there is glass nearby, there is a high chance of them colliding on it.

5. They don’t understand reflections

Birds have no understanding of reflection and its concept. That is why, when they see a landscape or sky reflected on the glass, they will assume it is accurate and fly through it. There are also cases when birds attack their reflections because they think they are seeing another bird and can’t make the connection that they are looking at themselves.

6. They are not used to vertical reflective surfaces

Glass is not something you can often see in nature; it is nearly nonexistent. But there is water, and they can see reflections of themselves on it, so why don’t they get confused? It is because they catch sight of it routinely and always expect to find water on ground level. Glass windows and doors, on the other hand, are reflective and vertical, which is unique and unfamiliar to them.

Frequently Asked Questions


Are you more curious about birds and glass? Many people who learned about this have the same questions about the topic. We have compiled some of them, and you can check them out below.

1. What happens when birds hit the glass?

They are usually as good as dead if a bird is flying at full speed with no resistance and hits a glass window. Their death might not be immediate since they can still fly away, but the bruising and internal bleeding is already severe.

2. Why do birds crash into glass more in the spring?

Spring is the start of the migrating and peak mating seasons. Courting males purposely attack glass as they perceive their reflections as competing birds. Younglings fly for the first time and explore a new environment, making them likely to crash on windows made of glass. There is more bird activity during these times since many species move for months simultaneously.

3. Can birds learn how to detect glass?

When a bird survives hitting a glass window, it will often remember not to fly through it the next time if it happens several times. However, they cannot still learn to distinguish other transparent or reflective obstacles.

4. What to do if a bird strikes your window?

Observe them from a distance. You don’t want to draw unnecessary attention that might put birds at risk in such a vulnerable state. If the bird is still alive, bring them to a safe place where it can recover. If they don’t get better after a few hours, they are more likely to die due to their injuries.

5. Do birds die when they hit glass windows?

The average velocity birds fly with when hitting windows is strong enough to render them dead. Many avians do not survive the impact of colliding with glass windows. The exact figure is unclear, but it reached around a third of a billion.


When you see birds hitting windows repeatedly, you will ask yourself, ‘why can’t birds see glass?’ and ‘can birds see glass?’ After reading this article, we hope you understand these accidents in many homes and business establishments better.

Have you ever seen a bird colliding with a glass window? Then you know why it happens and what you can do to prevent it from occurring again. Share this article with anyone who might need the information written here!

5/5 - (2 votes)

Clinton Atkins


Hi, I'm Clinton. Rocky and I became friends after a birdwatching trip with our new group. And we have been enjoying every adventure together. When he told me the idea of establishing a site that shares our experiences and fun, I immediately agreed. After trials and errors, here we have Thayerbirding.

You May Also Like

how long before birds come to a new feeder

How Long Before Birds Come to a New Feeder?

Bird feeding is such a popular hobby that the US has declared every February its ...

how much weight can an eagle carry

How Much Weight Can an Eagle Carry? (Lifting Weights by Species)

The eagle is one of the largest winged animals in the world. These birds of ...

how much weight can a hawk carry

How Much Weight Can a Hawk Carry? Answer Will Surprise You!

Hawks are known to be fierce predators that swoop in on their prey, which are ...

where do cuckoo birds live

Where Do Cuckoo Birds Live in Real Life? Get Facts Here!

Cuckoos are medium-sized birds that range from half a foot to three feet long. They ...

how deep should a bird bath be

How Deep Should a Bird Bath Be? – The Right Water Level Depth

How deep should a bird bath be? The water bath for birds should be 1 ...

best bluebird feeder

The Best Bluebird Feeders (Perfect for Mealworms Suet & Fruits)

Bird feeders for bluebirds are a surefire way of attracting these gorgeous backyard birds. Even ...