Orcas and Humpback Whales Spotted Fighting in the Pacific Ocean: 'Absolutely Unbelievable'

Mollie Naccarato, Sooke Coastal Explorations, PWWA

Crew members with the Pacific Whale Watch Association (PWWA) observed a rare, aggressive confrontation between a group of Bigg's orca whales and a pair of humpback whales spotted in the waters near the western Canada-U.S. border.

On Sept. 29, crew members on an Eagle Wing Tours whale-watching boat encountered the orcas first. The boat discovered around 15 orca whales "being unusually active at the surface," according to a PWWA press release.

Another whale-watching boat discovered two humpback whales interacting with the orcas shortly afterward, the association added.

"According to observers who came and went throughout the day, the encounter included an astonishing three hours of breaching, tail-slapping, and loud vocalizations before all of the whales disappeared into the fog, keeping the outcome of the melee a mystery," the PWWA said in its release.

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The encounter happened in the Juan de Fuca Strait, about 25 miles west of Victoria, British Columbia in Canada, and Port Angeles, Washington, according to the PWWA.

The association's executive director, Erin Gless, told the CBC that while it's "very common" for their boats to encounter both species of whales, spotting groups of both engaged "in the middle of a brawl" is much rarer.

Mollie Naccarato, Sooke Coastal Explorations, PWWA

"I'm still trying to wrap my head around it because it was absolutely unbelievable," Mollie Naccarato, a captain and naturalist with Sooke Coastal Explorations on Canada's Vancouver Island, told the CBC.

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"At first, the orcas seemed to be chasing the humpbacks," she said. "But then when there was space between them, the humpbacks would go back toward the orcas."

Naturalists with the PWWA identified some of the orca whales involved in the scuffle and the two humpbacks, who they know as BCX1948 "Reaper" and BCY1000 "Hydra," according to a statement. Gless told the CBC that the orca whales could be seen circling the two humpbacks and nipping at their flippers and tails.

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The orcas involved in the encounter often hunt marine mammals like seals, sea lions, and porpoises, and occasionally larger prey like humpback whales.

Mollie Naccarato, Sooke Coastal Explorations, PWWA

The PWWA stated that while the association "has not documented any fatal orca attacks on humpback whales in the Salish Sea," increases in both species' populations in the area could lead to more frequent confrontations.

"Orcas are the only natural predator that humpback whales have in this region," Gless told the CBC. "Even though humpback whales can get to be the size of a school bus, a group of very experienced hunters can attack [them]."

Whale-watching boats in the area are hopeful they will encounter the two humpbacks again before the animals swim south for their annual winter migration, the association wrote in its release. The orca whales involved in the encounter do not migrate and can be seen in the area year-round, according to the PWWA.