Dramatic Footage Captures 30 Orcas Attacking 2 Gray Whales in Five-Hour Battle Off California Coast

Shocking video shows a group of orca killer whales attacking two gray whales off the coast of Monterey Bay, California. For over five hours, a pod of more than 30 orcas are seen encircling the adult whales and trying to eat them alive.  Evan Brodsky of the Monterey Bay Whale Watch captured the wild drone footage on March 30. "Five hours of an attack by over two dozen Bigg's killer whales on two adult gray whales, and an attempted predation—which was unsuccessful!" he wrote on the group's Facebook page. "In over 30 years of documenting killer whales encounters by this is the FIRST time that such an attack has been documented on adult gray whales in Monterey Bay!!!" Read on to find out what happened during the attack and why it was so unusual.

"First of Its Kind" In 30 Years

Brodsky happened to witness the attack in the bay, about 120 miles south of San Francisco, and managed to record it. It lasted for nearly six hours, until the injured gray whales managed to escape their attackers and swim to shallower waters. "I have never witnessed anything like this in my life," he said.  Brodsky said it's not uncommon for orcas to attack gray whales, but they normally target the young, who are more vulnerable than full-grown adults. This attack was also unusual in that it happened in early spring, well before young whales reach the area. "Extremely rare encounter because usually the orcas with prey on the gray whale calfs this time of year," Brodsky noted on his Instagram account.

A Play-by-Play of the Attack

The California Killer Whale Project (CKWP) affirmed that this was the first documented time in 31 years that killer whales have attempted to attack adult gray whales in Monterey Bay. Gray whales can grow up to 49 feet long and weigh up to 90,000 pounds, the National Oceanic and Atmospheric Administration says.  "The first two hours the gray whales were together… the third hour the whales were separate and being attacked separately, and the last two hours one gray whale escaped to the beach and the second one was attacked for almost the remaining time," the CKWP said.

Killer Whales Usually Have Different Diet

Bigg's orcas, also known as transient killer whales, roam the Pacific Northwest and usually feed on smaller marine mammals, not other whales. "Transient Killer Whales, the type that we typically see here in Monterey, have a diet of other mammals, making springtime in Monterey Bay a haven for these tactically sound hunters," says Monterey Bay Whale Watch.  The video of the attack gives a rare look at an unusual hunt. Usually, mothers and their young remain close to the shore, where food is more available.

Commenters Cringe, Question Reason for Attack

"I still can't watch the whole thing. I'm happy the Greys got away & that this is a very rare occurrence!" one Instagram commenter wrote.  "Very very very unusual to see this kind of predatory behavior in wild mammals," said another. "I wonder if sea pollution and chemicals in the oceans are affecting the biochemistry health and behavior of killer whales. It doesn't sound like standard normal orca behavior either."

"I wonder if this "hunt" might have been a training exercise for many of the orcas. I know transients sometimes hunt seals and penguins with their young only to let them go after training has concluded," another commenter wrote.  "I bet there were some pissed off hungry and exhausted orcas after this," one woman opined.

Dolphins Seen Hunting in Bay

In happier visuals from Monterey Bay, last month Brodsky managed to capture footage of three dolphins deftly hunting a bait ball in the clear waters. The footage showed the dolphins "working together as a team," he said, maneuvering acrobatically through the water to make the bait ball tighter and tighter.  "Watching Pacific White Sided Dolphins hunt on a bait ball from the drone was so wicked," Brodsky noted.