Lorna Baker's day trip with her family to watch the capelin roll in Long Beach on the Bonavista Peninsula turned into something more extraordinary — a chance sighting of an oddly pink-hued whale.

"There was about 50 of us on the beach, and we looked at each other and were like, 'OK, everybody seen pink, right?'" Baker told CBC News.

"It felt amazing.… Nobody could believe what they were seeing."

The video she captured of three whales — one of them pink — went viral on social media in the days after, with many trying to solve the mystery.

Some commented that they had seen similar whales, or even the same whale, in different places this summer.

Baker said the two minke whales stuck around for most of the evening, while the pink one surfaced only twice and wasn't seen again that night.

"I know it's something I will probably never see again," she said.

Research scientist Jack Lawson of the Department of Fisheries and Oceans has some theories, and believes the pink whale is also a minke.

"Several weeks ago someone in Fort Amherst sent me pictures and video of a minke whale feeding there, and it was doing this behaviour where it was coming up from below the capelin there and breaching out of the water and smashing down its belly, and so on," Lawson said.

"And when it rolled on its side it had a nice pinkish hue to the belly. So I think, like us, if we jumped off a diving board many times and landed on our bellies we'd get this nice pink undercoating."

In addition, Lawson said, when most mammals physically exert themselves, blood is pushed to the periphery to help the animal cool off, which could explain the skin pigment change.

In whales, Lawson said, it's generally done through their flukes.

"But in this case it could be you're also seeing the pinkish skin coloration between the pleats on the belly as it's warm. It's working hard," he said.