Sharks can be 'social or solitary'

The most feared predators in the sea have individual personalities that affect how readily they socialise, according to a study by UK scientists. Individual sharks, studied in groups of ten, showed consistent social habits - either forming groups with other sharks or finding camouflage on their own. When a group was shifted into a new environment, individual sharks showed the same patterns of behaviour. This is the first study to show that sharks have their own personalities. The research was done in large tanks at the Marine Biological Association of the UK, in Plymouth, in collaboration with the University of Exeter. The findings appear in the journal Behavioural Ecology and Sociobiology. Strategies for safety Ten different groups, each containing ten small spotted catsharks, were each studied in three different situations. Some were complex environments with lots of rocks and other features, and some were simple tanks with gravel on the bottom. Continue reading the main story “Start Quote Imagine if we took ten work colleagues and plonked them in a bar, and observed which individuals sat together over the course of an evening” Prof William Hughes University of Sussex Even though the overall number and size of sub-groups among the ten sharks often changed between environments, the individual sharks that tended to form big groups continued to do so, no matter what the situation. Similarly, the more antisocial specimens remained on their own, or in much smaller groups. "The results were driven by different social preferences, that appeared to reflect different strategies for staying safe," said lead author Dr David Jacoby, a behavioural ecologist now working at the Institute of Zoology in London. "Well-connected individuals formed conspicuous groups, while less social individuals tended to camouflage alone, matching their skin colour with the colour of the gravel in the bottom of the tank," Dr Jacoby said. Prof William Hughes, an animal behaviour expert at the University of Sussex, said he was impressed by the level of detail in the results. "They recorded which shark was hanging around with which other sharks, on a number of occasions across two days - so they got a very, very detailed picture of the social relationships," he told BBC News.-READ MORE-http://www.bbc.co.uk/news/science-environment-29448192