Nepedia
Back to Discover
Fluent Reader
🧬

Blue shark

life science Maturity 5-7 Next article →

The blue shark is a beautiful and slender fish found in the deep oceans.

Blauhai (128648419) (cropped)
Blauhai (128648419) (cropped)

These sharks live in both tropical and temperate waters around the world. They can be found near every continent except for Antarctica. These sharks are often called the great blue shark. They have a special way of hiding called countershading. Their tops are a deep blue color. Their sides are lighter and their bellies are white. This helps them blend into the ocean.

Tiburón azul (Prionace glauca), canal Fayal-Pico, islas Azores, Portugal, 2020-07-27, DD 24
Tiburón azul (Prionace glauca), canal Fayal-Pico, islas Azores, Portugal, 2020-07-27, DD 24

Blue sharks have many amazing ways to sense their world. They use their eyes to see in both bright and dark water. Their eyes are placed on the sides of their heads. This lets them see almost all the way around them. They also have a lateral line to feel vibrations in the water. This helps them find the speed of currents and the movement of prey. They even have special sensors called ampullae of Lorenzini. These are tiny pores on their skin that feel electrical fields. These fields help them find food and avoid danger.

A Blue shark at the Uminomori Aquarium in Sendai
A Blue shark at the Uminomori Aquarium in Sendai

These sharks are very busy travelers in the sea. They migrate across huge distances to find food or stay in cool water. They prefer water between 14 and 16 degrees Celsius. They are often more active at night than during the day. During the day, they swim at a slow rate of about 1.2 kilometers per hour. At night, they speed up to about 1.8 kilometers per hour. They can dive deep into the ocean to find what they need.

Juvenile blue shark (cropped)
Juvenile blue shark (cropped)

Scientists have studied these sharks for a long time. We know from fossils that they lived a very long time ago. Some fossil teeth were found in Sri Lanka from the Miocene period. Other teeth were found in Chile, Italy, and Belgium. Today, we know they can live up to 20 years. They are viviparous, which means they give birth to live young. A mother can have a large litter of 25 to over 100 pups.

Prionace glauca in an aquarium
Prionace glauca in an aquarium

Blue sharks are an important part of the ocean's food web. They mostly eat small fish and squid. However, they can sometimes eat larger prey too. Other big animals like killer whales and tiger sharks may eat them. Because they are caught often in fishing nets, they are listed as Near Threatened. This means we must watch over them carefully. They are one of the most common sharks in the open ocean.

Blue shark, capture production, thousand tonnes, 1950-2022
Blue shark, capture production, thousand tonnes, 1950-2022
404 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (7)
File:Blauhai (128648419) (cropped).jpeg
Blauhai (128648419) (cropped).jpeg
File:Juvenile blue shark (cropped).jpg
Juvenile blue shark (cropped).jpg
File:Tiburón azul (Prionace glauca), canal Fayal-Pico, islas Azores, Portugal, 2020-07-27, DD 24.jpg
Tiburón azul (Prionace glauca), canal...
File:Pamtu - blue shark meat on sale in Malta (cropped).jpg
Pamtu - blue shark meat on sale in Malta...
File:Blue shark, capture production, thousand tonnes, 1950-2022.svg
Blue shark, capture production, thousand...
File:A Blue shark at the Uminomori Aquarium in Sendai.jpg
A Blue shark at the Uminomori Aquarium in...
File:Prionace glauca in an aquarium.jpg
Prionace glauca in an aquarium.jpg
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.