Study: White sharks form lasting communities, routinely get together for feasts

SYDNEY — Great white sharks are largely depicted as malicious, scary creatures in popular culture and media, but at the end of the day they just want to get together with some friends and socialize like the rest of us. In fact, according to a groundbreaking new study conducted at Macquarie University in Sydney, Australia, white sharks get together a few times each year with the same group of friends for a hearty meal of baby seals.

Make no mistake, great white sharks usually travel and hunt alone, but that doesn’t mean they don’t appreciate the occasional party. Scientists have known for some time that large groups of white sharks eating together tend to pop up sporadically, but up until now the scientific community had assumed these dinner parties were a completely random result of individual sharks traveling to areas filled with food.

Now, a research team led by behavioral ecologist Stephan Leu have discovered that many of these sharks actually know each other and have been getting together for years. Working in collaboration with researchers from Flinders University, the Fox Shark Research Foundation, and the French research organization CNRS, Leu and his team took photographs of nearly 300 white sharks for four and a half years. The sharks were photographed meeting close to a seal nursery off the coast of the Neptune Islands in the Great Australian Bight.

Through the use of photo identification and network analysis technology, researchers were able to identify and keep track of each individual shark that visited the area. To their surprise, they noted that many of the same sharks were observed in close proximity to each other time and time again over the course of the observation period. So much so, that researchers say there is no way it was simply a coincidence.

“Rather than just being around randomly, the sharks formed four distinct communities, which showed that some sharks were more likely to use the site simultaneously than expected by chance,” Dr. Leu comments in a release. “The numbers varied across time, and we suggest that sex-dependent patterns of visitation at the Neptune Islands drive the observed community structure. Our findings show that white sharks don’t gather just by chance, but more research is needed to find out why.”

On a related note, it seems sharks aren’t the only aquatic animals with a penchant for get togethers; another recent study conducted at Macquarie University found that manta rays regularly form close-knit and structured relationships that could also be described as communities.

The study is published in the journal Behavioral Ecology and Sociobiology.