Sand Tiger sharks have complex social networks: Study

Sand Tiger sharks may have a more complex social structure than anyone would have thought, a recent study has reported.

Using tracking devices, American Geophysical Union researchers found that Sand Tiger sharks form complex social networks that are typically seen in mammals but rarely observed in fish.

Danielle Haulsee, a PhD candidate in oceanography at the University of Delaware in Lewes said, the higher-order decision-making processes are often associated with mammals, or species that we think of as really smart - dolphins, elephants, or chimpanzees.

He added that he along with his research team used acoustic tags to track the movements of over 300 individual Sand Tiger sharks and recorded shark-shark interactions over the course of a year. Previous studies have looked at shark interactions in laboratories or species contained in pens, but this was the first study to record interactions for almost a year in free-swimming sharks.

According to Haulsee, Sand Tiger sharks, top predators that live in coastal waters off the Eastern United States, have experienced drastic population declines over the past several decades. Sand tigers are important regulators of marine food webs but have been historically understudied.

Research found that the groups of Sand Tigers stay together for certain times of the year and fall apart during other times. They also found that Sand Tigers re-encounter the same sharks throughout the year.

The researchers hope to use their results to answer questions about whether Sand Tigers form family groups or whether sharks of similar size and sex form distinct groupings. They also hope that defining critical locations where sharks congregate together will help build conservation plans to better protect this species.

The study is published in the 2016 Ocean Sciences Meeting.