See Pesto the viral baby penguin grow up as he sheds brown feathers in new pics

Pesto is growing up!

After reaching stardom in September, the king penguin chick is beginning to shed his brown feathers in exchange for new waterproof ones as he transitions into adulthood.

Pesto, who lives at the Sea Life Melbourne Aquarium in Australia, is nearing the final stages of his first molt. It's a crucial phase in a king penguin's life because it signifies the start of independence as they prepare to leave the colony, according to the aquarium.

King penguin chicks experience their first molt around 10 months old and the process can last up to six weeks, per the aquarium. Since molting requires baby chicks to use a lot of energy, the animals often lose weight as they form their new, sleek feathers.

“As Pesto sheds his juvenile feathers and develops his sleek, waterproof adult plumage, he’s beginning to look more like an adult king penguin and is almost ready to dive into the next stage of life as part of the colony,” a rep for the Sea Life Melbourne Aquarium shares with TODAY.com.

Growing these new feathers will allow Pesto to eventually swim. While king penguin chicks' brown feathers are insulating, they are not waterproof, which is where their adult plumage comes in handy.

The aquarium expects him to begin swimming with other king penguins as soon as the molting process is done, according to their website. But for now, Pesto is rocking his "mid-molt" look for the world to see.

Pesto became an A-list animal celebrity earlier this year, thanks to his big lifestyle, eating up to 25 fish a day, as well as his adorable appearance.

The Melbourne-based aquarium even hosted their own gender reveal in September for the penguin — and his fans, of course.

Many of the other penguins at Sea Life Melbourne Aquarium has taken an interest in Pesto, per the aquarium's website. His biological father, Blake, is the oldest and biggest penguin at the facility.

This story first appeared on TODAY.com. More from Today:

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