They had previously been tracked over the years by the study's co-author Dr Mauricio Hoyos-Padilla, from Fins Attached Marine Research and Conservation in Colorado Springs.Īround three dozen of these showed up on another great white's super social tag. The device was equipped with a video camera and an array of sensors that recorded a host of movements, including changes in acceleration, depth, direction - and even how rapidly the shark turned while swimming.ĭr Papastamatiou said: 'What put the "social" in this specific tag was special receivers that could detect other tagged sharks nearby.' It collected data for up to five days before popping off the shark's dorsal fin and floating to the surface. The researchers therefore combined different commercially available technology into a 'super social tag'.
Gathering seasonally around Guadalupe Island (pictured), researchers found the sharks joined up to check out seal colonies, with some spending more than an hour together Researchers believe this is why forming social associations might be so important, because it increases the ability to take advantage of another shark's hunting success. It showed both a turtle and a sealion separately evading a prowling great white.ĭr Papastamatiou said: 'This isn't unique to white sharks, since predators are unsuccessful a lot of the time when hunting.' The challenge of the hunt was reflected in the video footage, analysed by FIU undergraduate Seiko Hosoki. There were also certain sharks that were more active during the day, and others at night. The great whites also had different hunting tactics some were active in shallow waters, while others preferred to be deeper down in the depths. The data showed that, for the most part, the sharks preferred to be in groups with members from their same sex.īut there was also a lot of variation between the predators, with one shark that kept its tag on for only 30 hours having among the highest number of associations: 12 in total.Īnother had the tag on for five days but only spent time with two other sharks. Six great whites were followed – three males and three females – over a four-year period. 'Biologging can start to reveal the secrets of the social lives of large sharks.' 'Sharks may stay in proximity of other individuals in case those individuals are successful in killing large prey. 'But there is a lot of variation between sharks in terms of how social they may be and how they behave. 'We showed sharks may form some strong associations – over a few days – with some individuals. 'We put tags on white sharks off Mexico that measured behaviour and time spent with other tagged sharks. They can travel through the water at up to 15 miles an hour.ĭr Papastamatiou said: 'Understanding the social dynamics of large marine predators in the wild is challenging. Great whites can reach 22 feet long and weigh more than 2.5 tonnes - with orcas their only rival in the food chain. 'Seventy minutes is a long time to be swimming around with another white shark.' 'But there were sharks where we found considerably longer associations, much more likely to be social associations. Lead author Dr Yannis Papastamatiou, of Florida International University (FIU), said: 'Most associations were short.
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