Scientists Crack Case of Whales With Kelp Hats

Researchers have observed over 100 whales wearing hats made of kelp and seaweed. Humpback, gray, southern, and northern right whales have all been seen playing dress up with the marine plants. Experts think they have discovered why.

A global habit

Previous scientific studies noted that whales sometimes play with seaweed, but these seemed to be rare events in the same places: where kelp and whale watching are both common.

Now, a research team has been able to study the behavior across a wider region. They have used drones to film whales along the east coast of Australia, capturing aerial footage of them playing with the kelp. They also studied social media posts of “kelping” from the northeast Pacific and North Atlantic Oceans. Their findings suggest that kelping is a global phenomenon.

Their drone footage shows whales actively looking for kelp and sometimes playing with it for over an hour. Analyzing their footage, the research team has come to two main conclusions. One, that whales sometimes play with seaweed just for fun, and two, that it feels good on their skin.

Four images of humpback whales playing with seaweed

Humpback whales play with seaweed. Photo: Jan Olaf Meynecke et al., 2023


Getting rid of hitchhikers

Barnacles and lice attach themselves to whales and irritate their skin. Kelp is quite a tough marine plant and its rough surface can be used to brush off annoying critters.

The seaweed also has antibacterial properties, so it helps reduce bacterial growth on the surface of the whale’s skin. Furthermore, many baleen whales have sensory hairs around their jaws and head. Whirling through kelp likely creates a tickling sensation that might be soothing for them.

Frolicking through the seaweed is also a social activity. Sometimes, whales roll and lift patches of seaweed together, which enhances social bonds and aids learning.

“This is about coordination, mobility, and the enjoyment of having something to play with,” Olaf Meynecke, lead author of the study, told Live Science.

Some whales also bite the seaweed and pull it down into the water. Biting down is highly unusual for baleen whales because they are filter feeders.

“To bite something is not a natural instinct,” said Meynecke. He suggests that the whales could be trying to scrub the inside of their mouths.

Rebecca McPhee

Rebecca McPhee is a freelance writer for ExplorersWeb.

Rebecca has been writing about open water sports, adventure travel, and marine science for three years. Prior to that, Rebecca worked as an Editorial Assistant at Taylor and Francis, and a Wildlife Officer for ORCA.

Based in the UK Rebecca is a science teacher and volunteers for a number of marine charities. She enjoys open water swimming, hiking, diving, and traveling.