Blue sharks inhabit the deep waters of the warm and temperate oceans. They are known to be very fast swimmers, reaching speeds up to 43 miles per hour. Blue sharks feed on small fish and squid and can live up to 20 years. They can range from 6 feet up to almost 11 feet long, the longest blue shark reaching up to 20 feet. An interesting fact about blue sharks is that they normally range from 60 pounds up to 450 pounds, but the heaviest blue shark ever recorded was 862 pounds. Blue sharks live off all the coasts of every continent, except Antarctica. Blue sharks are not known to bite or attack humans, which up until now, there have only been about 13 biting incidents.
Blue sharks were considered not threatened, but until recently they are now considered near threatened. Young blue sharks are often eaten by larger sharks, like the great white shark and tiger shark, and even orcas. Sea lions and seals have been seen to feed on blue sharks as well. Blue shark meat is not widely sought out for, but the skin is used for leather, the fins for shark-fin soup and the liver for oil, like what most sharks are used for when killed. Aquariums cannot keep blue sharks because they tend to not do well in captivity, with most not living past three months in captivity and the longest being about a year old.