Blue shark

 

 

Average speed: 43 mph

The great blue sharks are the most widely distributed mammals in the world. They inhabit deep waters in temperate and tropical oceans. They are believed to live for more than 20 years.

Although generally lethargic, they can move very quickly. Small bony fishes, as well as squid, make up most of their diet. Additionally, they are opportunistic feeders and have been known to feed from gill nets and scavenge dead marine life.

They often gather in schools segregated by sex and size, which has led to their nickname "wolves of the sea". Great blue sharks are the most heavily-fished sharks. About 10 to 20 million individuals are killed each year. Blue sharks are not considered an aggressive species and rarely attack humans.