Killer Whale - this population of killer whales feed on herring (Orcinus orca). Tysfjord, Norway. In the autumn, schools of herring enter fjords of the NW coast of Norway and pods of killer whales follow the herring. To feed, the orcas surround the herring, forcing the fish into a tight ball, and with their tail, slap the fish at the periphery of the ball to stun or kill them. Then they pick up the herring one by one. This technique is called 'carrousel feeding'. On this image, we see the panicked fish 'boiling' at the surface, an orca diving to feed, and a gull ready to pick up a fish.