Extraordinary footage shows where humpback whales go for a spa day

To someone who didn’t know better, it might have appeared that there was something wrong with the humpback whales, which rolled over and seemed to play dead on the sandy bottom in the azure waters off Bermuda.

But Andrew Stevenson, a veteran free diver, knew exactly what he was witnessing after he "slipped off the boat and just started swimming around."

Stevenson, using a camera borrowed from his daughter, was capturing perhaps first-of-its-kind footage of two humpback whales utilizing a deep patch of sand as sort of a spa treatment, most likely to exfoliate but perhaps also for the mere sake of pleasure.

"The two humpbacks were rubbing their backs, sides, pectoral fins, flukes, noses, chins, tops of their heads, armpits in the lovely Bermuda sand," Stevenson, who lives in Hamilton, Bermuda, stated on Facebook.

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The free diver added: "We know belugas do this, and gray whales and orcas, but I believe this is the first time anyone has witnessed, much less documented, the same behavior in humpbacks."

Humpback whale rubs its back on the sandy bottom off Bermuda.

Said Alisa Schulman-Janiger, a California-based whale researcher: "I have never seen anything like it. I am not too surprised to hear that they do this, though, as it makes sense. Grays love to roll on sand. But to capture it, from above and below… exquisite!"

At times the humpback whales can be seen stretching out on their backs, with their pectoral fins outstretched, clearly enjoying the coarse feel of the sand. Stevenson  compared them to “Labradors rubbing themselves down ecstactically on a carpet.”

The free diver is familiar with many of the whales that visit Bermuda. One of the whales in his footage is a female humpback first identified in Bermuda in 1984.