MONTEREY (CBS SF) – Dramatic footage shows a group of killer whales methodically ram, isolate and kill a gray whale calf passing through Monterey Bay with its mother, on Saturday.

The graphic attack was captured in its entirety on video by Monterey Bay Whale Watch, a company that organizes whale-watching excursions for groups led by marine experts.
 


 
 
The company posted the video on Facebook with a warning, and says this is the first time an attack was caught on video from start to finish.

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In the clip, a small pod of killer whales can be seen moving in just below the surface. The young whale desperately tries to escape while the mother rolls over to protect her baby, but the outcome is inevitable. The killer whales will have their meal.

It took about four hours for five orcas to batter and kill the calf, even as its mother tried to defend it.

The pair were traveling to Alaska during spring migration.

Whale Research Institute Director Joe Renard tells KPIX 5 the gray whales travel in groups.

“With the migration of 22,000 grays off our coast, they move in groups of mothers with babies, teens, singles,” explained Renard. “Adult Males all go at different times.”

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Whales are seen in greater numbers in San Francisco Bay too. Ferry boats are constantly on the lookout.

“We’ve seen them in high traffic areas and in really shallow water,” said ferry deck hand Jason Blare. “The last one the skipper and I saw, we saw it right off the Berkeley Pier in 12 feet of water.”

Renard said with the large number of gray whales offshore, it was unlikely the orcas would need to chase anything past the Golden Gate Bridge into the Bay. Renard said the attack captured on video was simply an example of “the circle of life.”

“It’s wildlife. It’s nature,” said Renard.

“The California coast is super rich in wildlife and this is not really unexpected,” said Blare.

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Experts say Monterey Bay is especially dangerous for gray whales at this time of year. Killer whales frequent the area searching for food as the grays travel through during spring migration to Alaska.