Blue is a common color for many species of fish. Some of the most well-known blue fish include blue tang, bluegill, bluefish, and neon tetra. The vibrant blue coloration serves several purposes for fish including camouflage, communication, and attracting prey.
Common Blue Saltwater Fish
In the ocean, blue coloration helps fish blend in with the blue water and avoid predators. Many popular aquarium fish have striking blue hues. Here are some of the most popular blue saltwater fish:
- Blue tang – This bright blue surgeonfish gets its color from unique pigment cells. They are popular but need a large tank.
- Blue hippo tang – Close relatives of blue tangs, these fish have a bold blue front half and brown back half.
- Blue devil damselfish – One of the most brilliantly colored damselfish, they are territorial and moderately hard to care for.
- Blue chromis – Tiny fish that form large schools and add pops of blue to a saltwater tank.
- Neon gobies – Tiny fluorescent blue fish that glow under aquarium lighting.
- Blue damsels – Active fish that add sparkling blue hues. Damsels can be aggressive toward each other.
- Bluefin damselfish – The bright blue fins set these fish apart. They are very active but can be territorial.
- Regal tang – Brightly colored yellow and blue fish. They need plenty of vegetable matter in their diets.
These fish originate from tropical oceans around the world. Caring for them requires a large saltwater tank with strong filtration and regular water changes. Their bright colors and active nature make them popular for aquarists wanting to add some blue to their tanks.
Common Blue Freshwater Fish
While less common, some freshwater fish also have striking blue coloration. Here are a few of the most popular blue freshwater fish:
- Electric blue jack Dempsey – A color morph of the jack Dempsey cichlid with neon blue highlights.
- Blue acara – A South American cichlid with bright blue scales and fins.
- Blue gourami – A peaceful gourami species with powder blue coloration.
- Neon tetra – Small schooling fish with unmistakable glowing blue stripes.
These fish come from rivers and lakes in South America and Africa. They need large aquariums, warm water, and good filtration. Blue freshwater fish are more unusual than their saltwater counterparts but stand out wonderfully in planted community tanks.
Dull Blue Camouflaged Fish
While bright blue fish grab our attention, many species have duller blue tones that help them blend into their surroundings. This camouflage helps them avoid predators and sneak up on prey. Here are some of the most common drab blue fish:
- Bluebanded goby – A small eel-like fish with blue bands running vertically down its body.
- Sapphire devil damselfish – Most of its body is dull blue, helping it hide in coral reefs.
- Bluespotted cornetfish – A long thin fish with blue spots useful for camouflage when hunting.
- Bluestriped fangblenny – Their blue patterning lets them disappear into reef crevices.
- Catalina goby – Bottom-dwelling fish with dull blue tones matching the substrate.
While not as immediately eye-catching, these more subtle blue fish have an understated beauty. Their ability to camouflage using blue hues helps them survive in the competitive underwater environment.
Blue Fish Found Worldwide
Blue fish have evolved all over the world, on every continent. Here are some of the most widespread blue fish species:
| Fish | Locations |
|---|---|
| Bluegill | North America |
| Blue catfish | Rivers in North America, South America, Europe, and Asia |
| Blue shark | Temperate and tropical oceans worldwide |
| Bluefish | Atlantic, Indian, and Pacific Oceans |
| Blue tang | Coral reefs of the Indo-Pacific |
| Bluefin tuna | Atlantic Ocean and Mediterranean Sea |
As you can see, blue fish live on every continent and in most environments. The widespread nature of blue coloration shows it is beneficial and has evolved independently across diverse species.
Reasons for Blue Coloration in Fish
There are several reasons so many species of fish evolved to have blue coloration. Here are some of the main benefits:
- Camouflage – Blue provides camouflage in the blue waters of the open ocean, helping fish avoid predators.
- Communication – Many fish species use blue spots, patterns, and fins to communicate with each other.
- Attracting prey – Some fish use blue lights or spots to lure in smaller prey animals.
- Warning coloration – Vibrant blue can signal toxicity or poor taste to deter predators.
- Courtship displays – Intense blue coloring helps attract mates during spawning periods.
Blue coloration seems to have evolved separately many times over the long evolutionary history of fish. It provides a clear survival advantage in a variety of ocean and freshwater environments.
Most Brilliant Blue Fish
The most dazzlingly blue fish species include:
- Electric blue jack Dempsey – Their metallic blue glow makes them stand out dramatically.
- Neon blue goby – Tiny fish with an intense blue neon glow.
- Regal blue tang – Their bright royal blue bodies contrast with bold yellow trim.
- Blueface angelfish – These fish have extraordinary royal blue faces.
- Sapphire damselfish – Shimmering blue bodies help them stand out.
These fish make a memorable impression with their striking and intense blue colors. They are some of the most brilliantly blue specimens living in the world’s oceans and rivers.
Conclusion
Blue coloration has evolved in many diverse fish species across the globe. Blue helps fish camouflage, communicate, attract prey, deter predators, and find mates. Some of the most popular blue fish kept in home aquariums include blue tang, blue chromis, blue gourami, and neon tetra. Vibrant blue electric blue jack Dempseys and sapphire damselfish are among the most brilliantly colored blue fish. Whatever environments they live in, blue fish add visual interest and beauty wherever they swim.
