The whale watching in Monterey Bay off the California coast has been nothing short of spectacular lately with the presence of orcas, gray whales and humpback whales.

But what has whale experts amazed is the unprecedented hunting display put on by a pod of marauding orcas over a seven-day span.

On Wednesday, nine orcas attacked a gray whale calf right in front of a whale-watching boat, marking the fourth kill by the orcas in seven days in Monterey Bay, according to SFGate.

Monterey Bay Whale Watch called it a record number of predation events, and the same nine killer whales were involved each time with other individuals mixed in with them.

Marine biologist Nancy Black, who has been studying the whales in Monterey Bay for 30 years, called the phenomenon unprecedented.

"This has never happened in my thirty years,” Black told SFGate. “Just to witness that out in nature when you usually see that kind of thing on television is really spectacular.”

The Monterey Bay Whale Watch sightings log for Wednesday noted nine killer whales feeding on a gray whale at 9 a.m. and again at 2 p.m.

Though it is difficult to discern, the pod of nine orcas hunting a gray whale calf begins at about the 30-second mark in the video posted by SFGate:

This hunt was uncharacteristic from others, which typically take from an hour to a few hours, Black told SFGate. The gray whale mother and calf appeared skinnier and weaker than others, enabling the orcas to complete their hunt in 20 minutes.

"This was almost a record or how quick the killer whales attacked the mother and calf," Black told SFGate.

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The orcas return to Monterey Bay this time each year to prey on the migrating gray whales and their calves, considered to be a "very important food source for these killer whale families," writes Monterey Bay Whale Watch.

Lately, they've been getting their fill.

“These nine whales must be very full yet continue to eat,” Black told SFGate. “I expect they will become even more social in upcoming days as they [usually] do after stuffing themselves.”