(CNN) — An extraordinarily close encounter between a scientist and a killer whale has been captured on camera.

Filmed in the waters of Antarctica, the astonishing footage shows the young mammal headbutting marine expert Regina Eisert's camera, described as a "whale selfie stick."

The creature then opens its mouth and chews on some toothfish before swimming away.

The video was shot during an expedition in the Ross Sea region Marine Protected Area earlier this month.

Eisert, who is based at the University of Canterbury in New Zealand, was standing by the edge of the sea ice, collecting samples, when she was approached by the whale.

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Killer footage

The researcher has been studying Type-C killer whales in the region in order to better understand their population size, as well as where they live and what they eat.

And judging by the footage, toothfish are definitely a part of their diet.

Eisert was thrilled by the meeting and even suggested that the whale had been offering her some of his food.

"Killer footage confirms toothfish on the menu," she wrote in an Instagram post alongside the video. "And the whales are happy to share.

"A young killer whale approached us on the sea ice in Antarctica to offer us a piece of toothfish. I love these guys."