What colors can Fish see? Fish Vision vs Human Vision Explained 2023

Fish are aquatic animals that have been on Earth for more than 450 million years. Everyone in their life catches fish of different species or families.

So, have you ever been fascinated on can fish see colors or how they see the world? If yes, then you’ve landed on the correct page.

The answer to the question “What colors can fish see,” is: Fish can see colors depending on their species. On one side, Goldfish are tetrachromatic and can see all four-color spectrum UV light, blue, green and red shades, whereas Sharks are completely colorblind. Therefore, various fish species perceive colors in different ways.  

It is an immense topic to discuss, and scientists have proved the vision of some fish families. Hence, in this post, we have explained the fish vision and what colors they see. So, without any further ado, let’s begin.

What colors can Fish see?

Many fish can see four colors: Ultraviolet light, blue, green, and red. Their vision can perceive a much wider electromagnetic spectrum as compared to humans. However, how fish sense colors it’s dependent on their species. For example;

Tetrachromatic Vision- Many fish like Goldfish are tetrachromats. It means they can see millions of color shades that even humans can imagine. The rods and cones in their eyes are sensitive to UV, blue, green and red spectrum of colors.

Trichromatic Vision- Some fish like cichlids are trichromats and distinguish the colors as same as humans. It represents that the rod and cones in their retina can differentiate three colors, blue, green and red. Like humans, they don’t have the capability to perceive ultraviolet lights.

Dichromatic Vision- Other fish species like largemouth bass, Micropterus salmoides and reef fish are dichromats. It means their cones are highly sensitive to red color shades. They see the world mostly in a blue-green variation of the spectrum.

Monochromatic vision / Color-blindness- Deep-water fishes like Sharks have a monochromatic vision, or we can illustrate that they are completely colorblind. They catch the world only in gray shades.  

So, why do different kinds of fish have various visions? It is because of their environment. Fish eyes evolve on how deep they swim in the water.   

When light enters the water, it either scatters or absorbs, which results in the decrease of intensity and changing of colors.

In simpler terms, water attenuates different colors at a particular level of depths according to the wavelength.

Color with the longest wavelength like red absorbs or scatters first, then orange and yellow, then green and blue shades attenuate in deeper.

However, in the deepest part of the ocean, no color/light reaches, and there is only darkness.

Most of the fish that swims at the water’s surface have a tetrachromatic vision.

In contrast, the fish species that tend to swim at a particular depth are either trichromatic or dichromatic; however, unknown deep ocean species have a monochromatic vision or are completely colorblind because, in the complete darkness, they don’t need colorful visions to navigate.  

Hence, in a nutshell, fish vision is dependent on “at which level they swim.“

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What colors can Fish not see?

Some fish, like catfish, have poor eyesight and cannot see red color and ultraviolet light. 

In contrast, Goldfish and Zebrafish are tetrachromats and can witness every possible color variation. However, deep-water fish, sharks, and whales are completely color blind and cannot respond to any color. 

In a nutshell, it’s totally dependent on the fish species and habitat whether they see a particular color. In contrast, humans can distinguish colors from 380 nm to 720 nm wavelength; however, fish perceive a much wider range of electromagnetic spectrum depending on the species.

Some unresearched species may distinguish even more colors than we think. Over the millions of years of evolution, many deep-sea creatures have developed advanced vision, where rather than witnessing the color of a particular object without even seeing. Their eyes are capable of sensing wavelength. For example, Octopus.

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How do Fish see underwater?

The purpose of the fisheye is to see underwater. Like humans, their eyes comprise a cornea, an iris, and a pupil, but they are all covered under a protective film that helps them see more clearly underwater.

However, the catch is their eyes are designed to work underwater, not in the air. 

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How do Fish see underwater in the dark?

Fish with good vision can see in low-light conditions much better than humans, but mostly, they rely on Neuromasts.

It comprises sensory cells which assist them in detecting the slightest underwater movement by deflection. In this way, they can minimize the usage of the brain to take rest at night.

Some deep-water fish living in total darkness depends on ultraviolet light to see or lure their prey. In this way, we can estimate that fish can see at night or in the dark.

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Can Fish see fishing line?

Yes, fish can see the fishing line, and it is totally based on which type of fish you are targeting. There are three types of fishing lines.

Monofilament- Monofilament fishing lines are widely used. They are the most visible and available in different color options. However, you have to choose the color depending on the depth you are targeting. For example, the red color has a long wavelength and can be used for any depth. Similarly, yellow and green colors are used for deep fishing.

Braided- Braided fishing lines have better properties but are not completely invisible to fish. Like Monofilament, color plays an important here too.  

Braided lines have some excellent properties, but being invisible is not one of them. If fishing with braided lines, you will have to pay attention to the color and choose a suitable one for a given situation.

Fluorocarbon- These types of fishing lines are used for deep water fishing and have excellent underwater invisibility properties.

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How do Fish see humans?

Goldfish and Zebrafish are tetrachromats and can see humans in a more colorful way along with ultraviolet lights.

On the other hand, sharks and whales can see humans only in black and white shades without any color. Many other species have the capability to see the world similar to humans.

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Fish vision vs Human vision

Fish Vision	Human Vision
Fish have tetrachromatic/trichromatic/dichromatic/monochromatic vision depending on species	Humans have trichromatic vision
They can see both underwater and on land.	We become near-sighted underwater.
Some species of fish have the advanced vision.	Humans have normal vision
Fish can see in the dark	Humans cannot see in the dark.

Here we conclude our article on, “what colors can fish see?” We hope you like this post. We will back with another post. Till then, stay tuned with us and read the articles below.

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Frequently Asked Questions-

Q1. What colors do walleye see best at night?

Ans. Walleye can see bright colors like white, chartreuse or glowing colors best at night.

Q2. What colors do pike see best?

Ans. Like walleye, pike can also see bright colors like white, orange, green and chartreuse at best.

Q3. What colors do bass see best?

Ans. Bass can see bright, medium red to green colors at best.

Q4. What colors can betta fish see?

Ans. Betta can see colors similar to humans. However, it is noticed that Betta fish are more aggressive towards red color.

Q5. Can fish see at night/ can fish see in dark?

Ans. Yes, fish can see at night or in the dark. They have an ability to perceive ultraviolet lights helps them to navigate in low light conditions.

Q6. What colors do crappie see best?

Ans. Like pike, crappie can see bright colors like orange, chartreuse, and green at best.

Q7. Can salmon see color?

Ans. Salmon are trichromats and can see millions of color shades like humans.

Q8. Can fish see red light?

Ans. Tetrachromatic and trichromatic fish can see red light. For example, Zebrafish, Goldfish, salmon etc.

References-

Do fish see in color by CCMR

Fish Eyesight: Does Color Matter by Midcurrent

What Fish see and what they don’t by New Channel 9

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Also Read:

• How do Whales see the world 

• What do Octopuses see?