Few of us have been lucky enough to see penguins in the wild, but I reckon we'd still know an unusual one when we saw one.
Still, one wildlife photographer managed to capture an extremely unusual specimen on a recent trip, as he unveils pic of what he calls a 'never before seen' yellow penguin.
Yves Adams, the snapper in question, was heading up a two-month photography expedition through Antarctica and the South Atlantic when the tour stopped off at the wild islands of South Georgia.
Braving the wild ocean, the 43-year-old and his guests landed at Salisbury Plain to photograph their colony of more than 120,000 king penguins.
While Yves unpacked safety equipment, a group of the usually monochrome birds swam towards the shore but one unusual bird drew his attention.
Noticing that a youngster had a bright yellow plumage instead of the usual black feathers, Yves was quick to grab his camera and snap these never-before-seen images - obligingly, the bird put on a real show.
Yves, from Ghent, Belgium, said: "I'd never seen or heard of a yellow penguin before. There were 120,000 birds on that beach and this was the only yellow one there.
"They all looked normal except for this one. It really was something else. It was an incredibly unique experience.
"This is a leucistic penguin. Its cells don't create melanin anymore so its black feathers become this yellow and creamy colour.
"I was in charge of helping people with equipment and was one of the first people to land on the beach and was unloading the safety equipment and food when we spotted this group of king penguins.
"One of the birds looked really strange and when I looked closer it was yellow. We all went crazy when we realised. We dropped all the safety equipment and grabbed our cameras.
"We were so lucky the bird landed right where we were. Our view wasn't blocked by a sea of massive animals. Normally it's almost impossible to move on this beach because of them all.
"It was heaven that he landed by us. If it had been 50 metres away we wouldn't have been able to get this show of a lifetime."
Yves' tour with Quark Expeditions in December 2019 carried on for a further eight weeks, which meant he ended up with thousands of photos to trawl through. So maybe we shouldn't be too surprised that he's only released the photos now.
Yves said: "I was on an expedition for two months so I took thousands of photos during that time, especially as the time of year meant it never went dark in the Antarctic, which is why it's taken me so long to find these photos.
"I'd been dreaming of going to South Georgia for 30 years since I saw my first David Attenborough documentary and I saw these penguins.
"It was certainly worth it, even before we saw this yellow penguin. It was awe-inspiring to see thousands of these birds on a rock in the middle of this massive, wild ocean."
Featured Image Credit: Kennedy News and Media