A pod of about 30 orcas attacked and “badly wounded” two adult gray whales off the coast of California in a video taken that shows a rare case of predatory behaviour.
Monterey Bay Whale Watch videographer Evan Brodsky captured the dramatic footage in March using a drone, counted more than 30 orcas.
The attacked whales split up and eventually made it to safety in shallower waters after a 6-hour attack, Brodsky wrote in an Instagram post.
Orcas (Orcinus orca), also known as killer whales, are the only major predators of gray whales (Eschrichtius robustus), according to the Alaska Department of Fish and Game.
But killer whales usually hunt calves rather than adults, opting to “take advantage” of calves that migrate up the coast with their mothers in the first year of their lives, Ari Friedlaender, a marine mammal ecologist at the University of California, Santa Cruz, told Live Science.
And even going after a young whale is no easy feat as the pod must still contend with its protective mother. Still, one attack doesn’t necessarily imply a troubling pattern, Friedlaender said.
“A single event is really something you don’t want to raise too big a flag over,” Friedlaender explained.
However, if orcas continue to attack adult gray whales, scientists might see the behavior as a sign of an underlying problem, Friedlaender continued.
For instance, one potential reason for orcas to continually attack adults is that significantly fewer gray whale calves are available. In that case, the attacks could signify an underlying problem with the gray whale population.
