A visitor might stumble upon a strange sight in Laguna, Brazil, if they went down to the shore. Here, the local fishermen rely on dolphins to help them with their yearly fish catch.
New research has found that just one local group of about 20 dolphins works with the fishermen, while the other local dolphins don’t cooperate, finding other sources of food. The researchers aren’t sure what separates these groups.
Scientists had known that dolphins work together to herd groups of mullet, a fish that’s an important source of food for local fishermen, toward a line of fishermen in boats or knee-deep water. Then the dolphins signal with specialized head or tail slaps when and where the fishermen should throw their nets. The cooperation is helpful to both parties, researchers said. The two wouldn’t survive without each other.