Australia's most famous penguin has only just turned one but may already have his eye on a lady friend.
The king penguin Pesto celebrated his first birthday at Melbourne Aquarium on Friday after going viral as an abnormally large chick.
He was visited by international pop stars Katy Perry and Olivia Rodrigo and even has his own Wikipedia page.
The "chonky chick" weighed more than 23kg at peak fluffiness but has shed his baby feathers and dropped to 14.6kg in the process.
Sporting adult feathers, Pesto has recently been following around a female penguin called Pudding and both are exhibiting "flirty" behaviours such as cleaning one another.
Keepers are wondering whether romance is abloom, although the monogamous creatures don't typically start breeding until hitting five or six years of age.
Charlotte Barcas, a member of the aquarium's penguin team, described Pesto as a "social butterfly" but said he still liked to hang around with his parents.
"He's still a little bit of a baby but he's definitely an adventurous soul," she said.
The playful penguin, whose favourite foods are whiting, salmon and trout, remains easy to spot despite shedding his fluffy feathering.
"He's a big boy," Ms Barcas said.
"He's almost as big as his dad ... so he stands out just because he's a little bit taller than the rest of the colony.
"He also has his own wing band which identifies him specifically."
The aquarium marked Pesto's birthday milestone with a fish-filled jelly cake, special signs and plenty of bubbles, a favourite of his.
