Boaters watch ‘in awe’ as elusive species shows off rarely seen behavior. See photos

Whale watchers in Massachusetts were treated to a “spectacular” show by one of the largest and most elusive whale species.

People aboard the Oct. 6 Hyannis Whale Watcher Cruise observed a fin whale perform a high fluking dive , the group said in a Facebook post, calling it “one of the rarest” sightings of the season.

A high fluking dive is when a whale raises its tail vertically out of the water in preparation for diving deeper, according to the National Oceanic and Atmospheric Administration.

While some species do this often, fin whales, the second largest ocean species behind the blue whale, “rarely raise their tails on any dive,” NOAA says.

“We enjoyed spectacular looks at this animal and watched in awe as it arched for a dive, then slowly, slowly lifted its fluke all the way out of the water,” the group said in the Facebook post.

“I don’t think I’ve ever seen that…and I’ve seen a lot of fin whales!” one person commented.

Another observer called the sighting “ nothing short of dreamy .”

Fin whales are also “known for their speed and elusiveness,” the group said.

They typically travel in deep “open seas away from the coast ,” making them difficult to track, according to NOAA.

The fin whale was seen in the Stellwagen Bank National Marine Sanctuary, an 842-square-mile protected area in the mouth of Massachusetts Bay.

Hyannis Whale Watcher Cruises is a member of Whale Sense , an NOAA-sponsored program that educates commercial whale-watching companies on responsible practices.

Hyannis Whale Watcher Cruises is based out of Cape Cod, about a 70-mile drive southeast from Boston.

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