The blue shark has one of the largest ranges in terms of depths of the water. They can be found from the surface to the bottom. This type of adaption makes it easy for them to be able to find food. Blue sharks are known to migrate thousands of miles for food and for mating. This species of shark often is not found alone. Instead, they form groups based on their gender and on their size. They are often referred to as the "Wolves of the Sea" due to the complex levels of hierarchy that they form within their groups which highly reflects the behaviour of wolves. Due to their territorial instincts and their aggressive behaviours, divers have to be very careful around them. Many of the filmings of these sharks have been done with the divers in cages for the divers' own personal safety.