Sharks have distinct personalities

A new study published in the Journal of Fish Biology shows that sharks have distinct personalities. The study conducted at Macquarie University observed the presence of personality differences in the Port Jackson sharks (Heterodontus portusjacksoni).
A team of researchers from Macquarie’s Department of Biological Sciences, tested the sharks’ boldness and willingness to take risks. To test their theory researchers designed two behavior tests.
For the first test, sharks were placed in a tank with shelter and each individual was then timed to see how long it took for them to emerge from their refuge box into a new environment. The second behavior test exposed each shark to handling stress, similar to handling by a fisherman, before releasing them again and observing how quickly they recovered.
They found that individual sharks had distinct and consistent behavior when exposed to an unfamiliar environment and stress. Some sharks were consistently bolder than others. The results demonstrated that each shark’s behavior was consistent over repeated trials, indicating ingrained behaviors rather than chance reactions.
Dr. Evan Byrne, lead author of the study said “This work shows that we cannot think of all sharks as the same.” “Each has its own preferences and behaviors, and it is likely that these differences influence how individuals interact with their habitat and other species.”
“We are excited about these results because they demonstrate that sharks are not just mindless machines. Just like humans, each shark is an individual with its unique preferences and behaviors,” said co-author Dr. Culum Brown, also from Macquarie University.
“Our results raise a number of questions about individual variation in the behavior of top predators and the ecological and management implications this may have. If each shark is an individual and doing its own thing, then clearly managing shark populations is much more complicated than we previously thought.” [Phys.org]