A recent study demonstrated for the first time that sharks have personality traits.
Researchers found some sharks exhibit highly social behavior while others are loners, the University of Exeter reported. The research team recorded the social interactions of groups of juvenile spotted catsharks in three different types of captive environments.
Scyliorhinus canicula sharks are found throughout the Northeast Atlantic and Mediterranean and have been observed to group together and rest on top of one another.
The sharks involved in the study were put in tanks of various levels of structural complexity.
"We found that even though the sizes of the groups forming changed, socially well-connected individuals remained well-connected under each new habitat. In other words, their social network positions were repeated through time and across different habitats," David Jacoby, a [behavioral] ecologist now at the Institute of Zoology, London said.
The results were based on different individual preferences such as social or antisocial behavior, which is believed to stem from the desire to stay safe. Social individuals tended to form conspicuous groups while hermits camouflaged and matched their skin to gravel substrates at the bottom of the tank.
Personalities are defined as repeated behaviors in numerous contexts, and this is the first time this phenomenon has been observed in sharks.
"In the wild these small juveniles can make easy prey items for larger fish, so different anti-predator strategies are likely to have evolved. More research, however, is required to truly test the influence of predators on social personality traits in sharks. This study is the first step in that direction," said Professor Darren Croft, of the Centre for Research into Animal Behavior in Psychology at the University of Exeter.
The study titled "Shark personalities? Repeatability of social network traits in a widely distributed predatory fish" was published Oct. 2 in the journal Behavioral Ecology and Sociobiology.
