Narwhals wield their iconic tusks in surprising ways — possibly even to play with living “toys.”

Few scientists have seen these so-called unicorns of the sea brandishing their tusks in the wild. Past aerial video has shown the Arctic whales swinging their “horns” to tap fish prior to eating them. Now they’ve been seen gingerly prodding and flipping a fish. These gentler movements may have been part of a play session, researchers report.

This is the first report of narwhals (Monodon monoceros) apparently sporting around for fun, says Greg O’Corry-Crowe at Florida Atlantic University in Fort Pierce. A behavioral ecologist and geneticist, he headed the research team. His group shared its new findings February 28 in Frontiers in Marine Science.

A narwhal’s tusk is an elongated, spiraled tooth. It protrudes from the top lip of males (and some females). Males can grow to 5 meters (16 feet) long, with their tusks spanning another half their body length.

Biologists suspect those tusks evolved so that males could show off or compete for mates. But past research has found they can offer other benefits, too. For instance, the tusks can sense changes in water temperature and salinity.

Technologies involving genetics, satellite tagging, aerial counts and mapping have offered insights on these elusive whales. Still, they provided only snapshots of what these unusual animals do, says O’Corry-Crowe.

So he decided to try what he calls an “old-style natural history and behavioral observation.” But not totally old-style. His team enlisted a remotely operated flying drone. Then they spent hours in the summer of 2022 filming narwhals as they swam in an island bay in the Canadian High Arctic.

One recording captured three narwhals chasing several Arctic char (Salvelinus alpinus), a type of fish. The whales sometimes swung their tusks like baseball bats to thwack fish — stunning them — before chowing down on them.

Another recording showed three narwhals following a large char, with one whale taking the lead. It lightly nudged and flipped the fish with the tip or side of its tusk. In this way, it altered the fish’s path. There’s little evidence that narwhals normally eat much char. And winter, not summer, is their big dining season. So this video seems to show the whale and fish investigating one another.

“There’s this tentativeness,” O’Corry-Crowe explains. Then, he notes, the char “makes a dramatic movement.” Afterward, the whale “just recoils and goes whoa!”

Moreover, he adds, that repeated tusk action — and the fact the whales didn’t try to eat the fish — suggest the narwhals were just playing.

Because of the Arctic’s harsh environment, people often think creatures there are constantly fighting to survive, O’Corry-Crowe says. But his team’s new study hints that sometimes these animals have time to explore, and possibly play — at least during their “summer vacation.”