The Blue Shark Is Built for Long-distance Travel

Sleek, fast, and unmistakably tinted with ocean hues, the blue shark is a standout among pelagic sharks.

Known scientifically as Prionace glauca, this wide-ranging shark species slices through temperate and tropical waters around the globe, making its home primarily in the open ocean. With their slender bodies and long, tapered pectoral fins, blue sharks are built for endurance and long-distance travel.

Often referred to as the "blue whaler," this species is a classic example of open-ocean adaptation. Its counter-shaded coloring — deep blue on top and white on the ventral surface — helps it blend into the watery world above and below, camouflaging it from both prey and predators.

Where Do Prionace glauca (Blue Sharks) Live?

The blue shark range includes the North Atlantic Ocean, Northeast Atlantic Ocean, Gulf Stream and parts of the Pacific, with some individuals even reaching waters off Costa Rica.

Blue sharks thrive in water temperatures between 54 and 72 degrees Fahrenheit (12 to 22 degrees Celsius), and they prefer the deep blue zones away from coastlines.

Because of their highly migratory nature, blue sharks can travel thousands of miles. They often gather in gender-specific schools, with female blue sharks sometimes found in different regions than males.

These long journeys expose them to varied marine environments — and a range of threats.

Are Blue Sharks in Danger?

Despite being one of the most widespread sharks, blue sharks are one of the most heavily fished shark species in the world. They are frequently caught in trawl nets and as bycatch in longline fisheries.

According to the International Union for Conservation of Nature, the blue shark is listed as "Near Threatened." Their population numbers are shrinking due to overfishing and habitat disruption, even though they are sometimes still marketed as sport fish.

It is not formally listed as a species of concern by the Food and Agriculture Organization of the United Nations. The peer-reviewed journal Marine Mammal Science has flagged them as a species of concern as well.

Like many shark species, blue sharks are vital to marine ecosystems. Their decline could ripple through the food chain, affecting everything from small fish to larger marine mammals. Protecting them isn't just good for sharks; it's good for the entire ocean.

What Do Blue Sharks Eat?

Blue sharks have a diverse diet, including small fish, squid and even other sharks. Their upper teeth are serrated for gripping slippery prey, while their lower teeth are more pointed. These adaptations allow them to tackle everything from slippery fish to more muscular meals.

Blue sharks are also prey. Killer whales (Orcinus orca), larger sharks like bull sharks and great whites (Carcharodon carcharias), and even sea birds have been known to take a bite out of these sharks, particularly juveniles.

Reproduction and Growth

Female blue sharks give birth to live young after a gestation period that can last up to a year. Their litter size is large compared to many shark species — sometimes over 100 pups.

Females mature later than males, and both genders rely heavily on their surrounding environment for cues on when to reproduce.

The lateral line system along their bodies helps detect vibrations and changes in the immediate environment, essential for navigation, feeding and even body language used to signal aggression or interest.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.