Explained: The Seal Reason The Kayaker Got Slapped With An Octopus

You've probably seen the footage that left you feeling a little stunned. Though perhaps not as stunned as the kayaker.

Now, you're wanting to know what really spurred on the feud between the seal, the octopus and the unsuspecting kayaker.

While it's not every day that Associate Professor Mary-Anne Lea witnesses one of the species she has studied for years hurl an octopus into a person's face, it's not exactly rare behaviour.

READ MORE: 'I Know Crazy Right': Seal Uses Octopus To Slap Kayaker In The Face

What you're seeing in the video, captured by local adventurer and phtographer Kyle Mulinder during a paddle off Kaikoura in New Zealand's South Island, is a New Zealand fur seal preying in its natural habitat.

"We'd call it a fairly common foraging strategy for fur seals, particularly when they're grappling with large prey," Lea, from the University of Tasmania's Institute for Marine and Antarctic Studies, told ten daily.

"They tend to bring it to the surface, thrash it from side to side essentially to stun it to make it easier to swallow."

New Zealand fur seals are found on rocky shores around the mainland, Chatham Islands and the sub-antarctic islands You'll also find them in eastern, western and southern Australia.

Mulinder was paddling around Kaikoura  with mates when he spotted ones of the guys fighting an octopus underwater. Before he knew it, he copped a face-full of octopus.

"I know, crazy right?," Mulinder wrote on Instagram.

"I'm not sure who got more of a surprise , the octopus or me."

A rather majestic looking New Zealand fur seal. Image: AAP

Octopuses are quite common prey items, particularly among male fur seals, based on their size. A 2016 DNA assessment of fur seal diets in New Zealand found octopuses were present at four of five sites in Kaikoura across winter and summer.

"An octopus is a little more challenging than fish. It's quite muscular, has long arms that can wrap around the face," Lea said.

"They're a prized prey item -- I don't think the seal intended to let go of it."

Often nocturnal foragers, fur seals have strong front flippers and chest muscles that help to project themselves from the water -- which helps to explain that remarkable outburst.

"They can't build that kind of speed underwater -- which only adds to the spectacle," she said.

It's one that Lea has seen before on satellite tagging projects at Campbell Island. But she says this one, particularly during the day, was rare.

"These are foraging events that we don't see commonly, because they're occurring out at sea," she said.

"You're always quite lucky to witness one -- perhaps not quite as closely!"