An estimated 64 blue whales have been spotted in Monterey Bay, California, on November 14, marking the first time in 30 years the mammals have appeared in the area in these numbers, according to reports.

Anne Frank, an employee at Monterey Bay Whale Watch told Mercury News, "In all my experience in 15 years here, I’ve never seen the number of blue whales we have right now. ”

In the video, the blue whales can be seen swimming alongside humpback whales, much to the delight of whale watchers on the boat. Credit: Monterey Whale Watch/Gowhales.com via Storyful