"WASHINGTON - Sharks have more complex social lives than previously known, as shown by a study finding that gray reef sharks in the Pacific Ocean cultivate surprising social networks with one another and develop bonds that can endure for years.
The research focused on the social behavior of 41 reef sharks around the Palmyra Atoll, about 1,000 miles (1,600 km) southwest of Hawaii, using acoustic transmitters to track them and camera tags to gain greater clarity into their interactions.
Far from being solitary creatures, the sharks formed social communities that remained rather stable over time, with some of the same individuals remaining together during the four years of the study."