Meet Pesto, the Biggest Baby Penguin This Australian Aquarium Has Ever Seen

Most adult king penguins weigh between 31 and 37 pounds. At nine months old, a 51.8-pound Pesto is already looming over his parents

Large fluffy penguin and a group of adult penguins
Pesto's fame took off after the aquarium threw him a gender reveal party earlier this month. Sea Life Melbourne Aquarium

In late January, caretakers at Sea Life Melbourne Aquarium in Australia were ecstatic when a king penguin chick successfully emerged from his shell. The baby, which they named Pesto, was the only king penguin born at the aquarium in the last two years. He weighed less than a pound.

They’ve since watched as the youngster grew—and kept growing. As of Wednesday, Pesto weighs a whopping 51.8 pounds, according to the aquarium. 

As Pesto has grown, so has his fanbase. The massive black-and-white bird has become something of a social media darling, racking up an impressive online following that could rival Moo Deng’s (a now-famous baby hippo born in Thailand).

Pesto has been on display at the aquarium since April, per NPR’s Rachel Treisman. However, it wasn’t until the facility threw him a gender reveal party earlier this month that his stardom really took off. (Humans can’t distinguish between males and females just by looking at them—they have to take blood samples.) Since then, his celebrity has skyrocketed.

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“We have seen an increase in social traffic, web traffic and of course footfall,” Michaela Smale, a senior keeper at the aquarium, tells 9News’ Maddison Leach. “People are no longer coming to Melbourne just for the shows, music and coffee. They’re coming to see Pesto.”

But why is Pesto so huge, literally speaking?

Caretakers chalk up his unusual size to a “hearty appetite”—he eats more than 25 fish a day—and good genes. His biological father, a king penguin named Blake, is one of the biggest and oldest penguins at the facility, weighing in at around 39 pounds, per New Atlas’ Bronwyn Thompson.

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However, Pesto is being raised by a younger couple, Tango and Hudson, who have been taking good care of him, according to the aquarium. For reference, they both weigh just about 24 pounds. As Jacinta Early, the aquarium’s education supervisor, tells BBC News’ Tiffanie Turnbull, Pesto “eclipses” the pair, “which also makes him look comically large.”

Right now, Pesto is still covered in fuzzy brown down. But in the coming months, his baby feathers will be replaced by black, white and orange plumage.

“He’s going to start losing that really adorable baby fluff,” says Early to the Associated Press’ Rod McGuirk. “It might take him one to two months to really get rid of it. Then he’ll be nice and sleek and streamlined.”

Around the same time, he may also lose some weight. As he matures, he’ll likely settle in at closer to 33 pounds, per NPR. Still, Pesto will probably always be a “big boy,” Smale tells CNN’s Lilit Marcus.

“He’s already significantly taller than his dad,” she adds.

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King penguins typically weigh between 31 and 37 pounds and stand between 33 and 37 inches tall. They are larger than most other penguin species—but they aren’t the largest. That title goes to the emperor penguin, which can weigh up to 100 pounds and stand 50 inches tall.

In the wild, king penguins live on Antarctic and subantarctic islands, including the South Sandwich and Falkland Islands. Between one million and two million breeding pairs live around the world—and according to the International Union for Conservation of Nature, their numbers are increasing. They’re considered a species of “least concern.”

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