Avian royalty is making a rare visit to the Kapiti Coast, north of Wellington.

An emperor penguin, from the Antarctic, has been spotted at Peka Peka Beach. The only previous recording of an emperor penguin in New Zealand was at Southland's Oreti Beach in 1967.

Department of Conservation (DOC) staff were first alerted by Kapiti resident Christine Wilton who was walking her dog yesterday afternoon at the beach.

"I saw this glistening white thing standing up and I thought I was seeing things," Ms Wilton said.

She contacted DOC's Waikanae office and rangers went to investigate.

They saw what looked like a big white ball in the sand. It stood up, looking quite relaxed and in good condition. It was later confirmed the majestic visitor was a juvenile emperor penguin, standing at about a metre tall.

DOC has advised people that they should not disturb the penguin and ensure that dogs were kept on leads in the area. Penguins can give vicious pecks if threatened. If left alone, it was expected that the bird would eventually swim back out to sea.

"It's amazing to see one of these penguins on the Kapiti Coast," said DOC biodiversity spokesperson Peter Simpson.

"Unusual animals from the Antarctic sometimes visit our shores, but we really don't know why."

Emperor penguins are the largest penguins, adults reaching more than a metre tall and weighing up to 30kg. They feed on fish, krill, squid and a wide range of marine invertebrates and can dive 450 metres deep and spend 11 minutes underwater.