Marine Life Encyclopedia
Sharks & Rays
Blue Shark
Prionace glauca
Distribution
Worldwide in tropical to cold temperate latitudes
ECOSYSTEM/HABITAT
Open ocean (pelagic)
FEEDING HABITS
Active predator
TAXONOMY
Order Carcharhiniformes (ground sharks), Family Carcharhinidae (requiem sharks)
Blue sharks are named for the striking blue coloration on their backs, making them the most distinctive of the requiem sharks. The contrast between their white underbelly and dark blue back is called counter-shading and helps provide camouflage for the shark as it swims in the open ocean. The blue shark is one of the most wide-ranging shark species, and can be found throughout all oceans, in both temperate and tropical waters, from the surface down to depths of about 3,280 feet. Reaching maximum lengths of around 12.5 feet long, the blue shark’s slender body and elongated tail fins help make them one of the fastest sharks in the world.
Blue sharks use their speed to prey on a wide variety of prey, including small bony fishes, such as sardines, and cephalopods like squid and octopus. These sharks are more social than some other pelagic sharks, and groups of blue sharks often come together to feed on large schools of prey, and individual sharks will use body language to signal aggression between each other. Blue sharks will also sometimes come together in gender-specific schools as juveniles while not feeding, though their reason for doing this is not yet known.
Blue sharks reach maturity at about five years old, and until then, juveniles typically stay in pupping areas of the sub-Arctic. Males initiate mating by biting a female between her two dorsal fins, which is why females have significantly thicker skin in this area than males do. Females give birth to live pups that are each around 15 inches long, with litter sizes averaging at 25-50 pups, though much larger litters have been documented. Though blue sharks are listed as ”Near Threatened,” they do make up 60% of all reported shark catches and singularly dominates both the fin trade and shark meat trade. Despite being considered one of the most abundant and resilient shark species, their populations are thought to be decreasing, with their decline intrinsically linked to the lucrative shark fin and growing shark meat trade.
To learn more about blue sharks, read Oceana’s December 2022 report.
Get Involved
Donate Today
SUPPORT OUR WORK TO PROTECT THE OCEANS BY GIVING TODAY
With the support of more than 1 million activists like you, we have already protected nearly 4 million square miles of ocean.
TAKE ACTION NOW
Support policy change for the oceans
Decision-makers need to hear from ocean lovers like you. Make your voice heard!
VISIT OUR ADOPTION CENTER
SYMBOLICALLY ADOPT AN ANIMAL TODAY
Visit our online store to see all the ocean animals you can symbolically adopt, either for yourself or as a gift for someone else.
DOWNLOAD OCEAN ACTIVITIES
HELP KIDS DISCOVER OUR BLUE PLANET
Our free KELP (Kids Environmental Lesson Plans) empower children to learn about and protect our oceans!