Humpback Whales Use Sandy Ocean Floor for Exfoliating ‘Spa Day’, Researchers Find

Humpback whales in Queensland, Australia, use sandy, shallow bay areas for an exfoliating “spa day”, researchers at Griffith University have found.

Footage recorded between August 2021 and October 2022 shows humpback whales appearing to roll around in shallow waters, scratching their skin on the ocean floor in the process.

The whales were filmed during their southern migration to cooler waters.

Researchers at Griffith University, led by Dr Olaf Meynecke, tagged several humpback whales with CATS tags, which feature high-quality video recording.

Using data and footage collected from the tags, whales were observed performing full and side rolls in water up to 49 meters deep on the sea floor lined with fine sand or rubble.

“Humpback whales host diverse communities of skin bacteria that can pose a threat for open wounds if bacteria grow in large numbers,” Meynecke said, “Removing excess skin is likely a necessity to maintain a healthy bacterial skin community. Humpback whales can remove some barnacles and skin through surface activity such as breaches but not all.”

Meynecke added that the rolling could also be part of the whales’ social behavior.

“During the different deployments, the sand rolling was observed in the context of socialising. The behaviour was either following courtship, competition or other forms of socialising,” Meynecke said.

“So we believe that the whales exfoliate using the sand to assist with moulting and removal of ectoparasites such as barnacle and specifically select areas suitable for this behaviour,” he added. Credit: Griffith University/Dr Olaf Meynecke via Storyful

Video transcript