Whale watchers aboard a small boat off Maui watched with widening eyes recently as a humpback whale suddenly turned toward them, began to slap her large pectoral fin on the surface, and struck their inflatable boat with its head.
The collision with the 25-foot vessel was more of a shove than a strike, but blunt enough to "toss our boat a good five feet when she hit," said Jennifer Nap, who videotaped the unusual incident while on the trip with her husband, Ryan.
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About 10,000 endangered humpback whales are in Hawaiian waters for the winter breeding and nursing season.
The Naps and their group were with Ultimate Whale Watch and had been following a mother and calf "from a safe distance," Nap said, when the mother whale suddenly turned.
The crew shut the engines down as the whale "came straight for us, I think to warn us to move," Nap said.
The calf had veered away from its mom, toward the vessel's bow. The mom, still on her side and slapping her pectoral fin, glided into the boat as the passengers reacted with trepidation and joy.
"As soon as she was done pushing us aside she dove under, then popped right back up on the other side with her calf," Nap said.
It remains unclear whether the bump was intentional. Flipper slapping is not typically used as a warning; a whale is more likely to violently slap its fluke, or tail fin, to signal its displeasure.
Plus, as researcher Alisa Schulman-Janiger points out, humpback whales almost always trumpet blow to issue warnings, and no such sounds can be heard in the footage.
Lee James, CEO for Ultimate Whale Watch, said the female humpback was also distracted by a male escort who was nearby.
"It is most likely that this mom was distracted with her calf and keeping another eye on a escort that was being a little irritating for the female, as escorts can be," James said. "We think she simply wasn’t paying attention and bumped the boat, then carried on pec slapping like nothing happened."
Researchers have stated on Facebook that this probably would not have occurred if the engines had been idling, because the noise would have let the whale know the boat was there.
In any event, the whale seemed to be OK and the passengers returned to port with lasting memories.
Said Nap: "An absolutely amazing scene."
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