Rare footage shows dozens of killer whales targeted two adult Gray whales in an 'never-before-seen' attack.<br /><br />Video shows two dozen Bigg's orcas joining together for the relentless attack - which lasted five hours.<br /><br />This was the first observed attack on adult gray whales in Monterey Bay in more than 30 years documenting encounters for the California Killer Whale Project.<br /><br />Researchers at Monterey Bay Whale Watch said: “Usually killer whales will hunt gray whale calves as they head up to their northern feeding areas with their moms. <br /><br />"But these were not calves - they were huge adult gray whales."<br /><br />The agency spokesperson added: “We were able to observe the unique hunting strategies of the pods and the rarely seen defensive strategies of the two Grays.<br /><br />“The battered gray whales eventually made it to shallow water, and the orcas broke off."<br /><br />Bigg’s orcas, formerly known as West Coast Transient orcas, are a subtype described by researcher Michael Bigg. <br /><br />They feed exclusively on marine mammals and tend to travel in smaller groups than so-called resident orcas.<br /><br />The incident was captured on video in Monterey Bay, California, USA, on March 30.
