Description & Behavior
Blue sharks, Prionace glauca (Linnaeus, 1758), aka blue dogs, blue pointers, blue whalers, great blues, great blue sharks, great blue whalers, sharks, and tribon blous, are large sleek/slender, pelagic (open water), blue-indigo-colored sharks. They have long, pointed fins, pointed snouts, and large eyes. Their elongated caudal fin (tail fin) provides swimming power as the tail moves side-to-side. The blue shark’s tapered body makes them very graceful swimmers. These sharks are among the fastest swimming sharks and are also known to leap out of the water. Estimates of their speed varies; some say that they can swim at about 97 kph, while more conservative estimates are about 35 kph. Blue sharks grow to be up to 4 m long, averaging 3.35 m, and can weigh up to 205.9 kg.
World Range & Habitat
Blue sharks are pelagic (found in open waters). Like most pelagic sharks, they are found worldwide. Atlantic blue sharks migrate east across the Atlantic Ocean each year, following the warm Gulf Stream waters. They travel a circuit from the Caribbean Sea, along the coast of the US, east to Europe, south to the African coast and back to the Caribbean. Blue sharks often form large, all-male or all-female schools which contain sharks that are about the same size; the reason for this unique social behavior is unknown.
Feeding Behavior (Ecology)
Blue sharks, Prionace glauca, are opportunistic feeders; however, their favorite meal is apparently squid.
Blue sharks are viviparous (the young are born live rather than from an egg). Litters consist of 4-135 pups; the number of pups increases as the size of the mother increases. Their gestation period is almost 1 year. Females are mature at 5 years of age. Blue sharks are known to live for at least 20 years.
Conservation Status & Comments
NEAR THREATENED (NT)
A species is Near Threatened when it has been evaluated against the criteria but does not qualify for Critically Endangered, Endangered or Vulnerable now, but is close to qualifying for or is likely to qualify for a threatened category in the near future.
References & Further Research
[ Photography ] Blue Shark Photographs – Golden State Images, Randy Morse
Ken Bondy Photographer
No Mako: Mistaken Identity Leads to Record Blue Shark for California Angler; ‘I was Thrown Off’
Shark’s record dive into the blue ~ Recently tagged male blue shark plunges 1250 m off the Bay of Plenty coast in a quest for a meal of squid
Research Prionace glauca @
Barcode of Life ~ BioOne ~ Biodiversity Heritage Library ~ CITES ~ Cornell Macaulay Library ~ Encyclopedia of Life (EOL) ~ ESA Online Journals ~ FishBase ~ Florida Museum of Natural History Ichthyology Department ~ GBIF ~ Google Scholar ~ ITIS ~ IUCN RedList (Threatened Status) ~ Marine Species Identification Portal ~ NCBI (PubMed, GenBank, etc.) ~ Ocean Biogeographic Information System ~ PLOS ~ SIRIS ~ Tree of Life Web Project ~ UNEP-WCMC Species Database ~ WoRMS