A surprise visitor has made a rare appearance on Plimmerton Beach, north of Wellington - but don't get too close.

A leopard seal, the likes of which have a history of animosity towards humans, has since Thursday made itself at home on the North Island's southern shoreline.

The Department of Conservation (DoC) had warned locals to stay well away from the animal, as it is capable of killing people if it gets sufficiently worked up.

They've asked people to keep a distance of at least 20 metres, refrain from making loud noises, throwing things, or attempting to feed or touch it. They also warn pet owners to be wary that their animals don't get too close.

Wiremu Bayliss, who took a video of the seal and posted it on Facebook, told Newshub the seal "was a beautiful thing to see" despite it being "a predatory creature".

"I've seen orcas, other seals and even [sting]rays, but that's a first for a leopard seal - stunning," he said.

DoC biodiversity ranger David Moss said the sighting of a leopard seal was "moderately rare", saying he'd only witnessed about three in Wellington in the past five years.

NIWA marine ecology technician Andrew Miller says leopard seals are "instinctively a predator".

"They're curious, and not used to being in close proximity to humans, which they might think is a penguin," he said.

Mr Miller said the species visits New Zealand coasts occasionally, though they're mainly spotted in Auckland and the Campbell Islands, south of Invercargill.

Last week, another leopard seal made headlines after it was snapped making a lengthy stop at Auckland's Westhaven Marina.

Newshub.