The Big Blue Ocean Exploration

Blue whale reveals a fluke, or tail, that resembles an airplane wing

Peculiar cetacean has been seen before and is nicknamed 'Delta'

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Blue whale nicknamed “Delta” reveals peculiar fluke off Dana Point. Credit for both images: Frank Brennan/Dana Wharf Whale Watch

A magical moment for whale watchers is when one of the gigantic cetaceans reveals its fluke, or tail, to signal a deep dive. But boat passengers in Southern California were treated to an extraordinary moment last week when a blue whale showed off a fluke that is shaped like an airplane wing.

Blue whale flukes are broad and triangular, as a rule. But both ends of this mammal’s fluke are turned upward, like winglets at the ends of a wing, in almost perfect symmetry.

The sighting was made aboard the Dana Pride, which operates from Dana Wharf Whale Watch out of Dana Point in Orange County, California. As it turns out, because of the blue whale’s peculiar fluke formation, it is easily recognizable and has been spotted before.

Its most common nickname is “Delta.”

“Delta is a new whale to me, but others say they’ve seen a lot of her over the years,” says Mike Makofske, a spokesman for the Orange County chapter of the American Cetacean Society.

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“I posted Dana Wharf’s photo on the ACS National Facebook page, and Dorris Welch of Sanctuary Cruises in Moss Landing said they’d seen her several times in early summer 2012, up in Monterey Bay.  Another poster, Diane Dahl Cullins, commented that she had a picture of the same whale taken two years ago off San Diego.”

According to the Cascadia Research Collective, the first sighting was in the Gulf of the Farralones west of San Francisco in 1987. The whale also has been sighted off Baja California and in the Santa Barbara Channel. (Click here to learn more about past sightings.)

Facebook user Eric Zimmerman posted: “On the [Santa Barbara-based] Condor Express we nicknamed it ’747′ after its large size and the way its fluke tips resemble the winglets found on the end of large airplane wings.”

About 2,000 endangered blue whales ply California waters seasonally, with the 2013 season apparently just getting underway. Delta is among the early arrivals, and where the mammal appears next is anyone’s guess.

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