Penguin's Cataract Surgery Saves His Vision

He was having trouble catching fish and was bumping into other penguins.

Munch the penguin after surgery
Munch the penguin after surgery.

Chester Zoo

A Humboldt penguin named Munch had first-of-its-kind surgery to save his eyesight at the Chester Zoo in the U.K.

Zoo conservationists noticed the 4-year-old penguin was having trouble catching fish and was bumping into other members of his colony.

“We spotted that Munch was swimming slower than normal and was struggling to dive for the fish at feeding times — and if a penguin can’t catch a fish then you know something is amiss. That’s when we called in the zoo’s vets," said Sophie Bissaker, parrots and penguin keeper at Chester Zoo.

After veterinarians examined the penguin, they found that Munch had cataracts which created cloudy patches on the lenses of each of his eyes. He had very little vision in his left eye and none at all in his right.

They decided only treatment by a veterinary ophthalmologist could save his eyesight. They transported Munch to the Eye Vet clinic in Cheshire, where he underwent a 2-hour procedure to have the cataracts removed.

Although cataract surgery is common for dogs and cats, it was the first time it had been done by the specialists on a penguin.

“I’ve been in the veterinary field for almost 24 years and Munch is the very first penguin I’ve operated on – they’re not regular clients that’s for sure," said veterinary ophthalmologist Iona Mathieson who performed the surgery. "Unfortunately, because his quality of life was impacted by the diminished sight, surgery was the only option we had available to us."

Because the specialists were aware of how the zoo had been greatly impacted by the pandemic, they donated their time and equipment. They also approached several companies that made items necessary for the surgery for donations as well.

The surgery was successful and doctors say Munch is on his way to making a full recovery.

“Like many of the staff at the zoo, our team has worked throughout the national lockdowns, so we’re all feeling mentally and physically exhausted, but taking care of Munch was just the morale boost that we all needed," Mathieson said. "It’s an amazing feeling knowing that we’ve helped save him, he’s the first thing that made me smile in a long time and caring for him was definitely the best part of my year. We can’t wait to visit him and the penguin colony now that the zoo has reopened.”

Recovering with a Friend

After his procedure, Munch was kept in a shallow, nursery pool so the keeper could monitor his progress. His best friend, Wurly, kept him company while he recovered.

“It was important for Munch to have time away from the rest of the group for a couple of weeks following his surgery while we regularly checked up on him," Bissaker said. "But, penguins live in tight-knit colonies and like to be with other birds, and so we decided to provide Munch with some company with his life partner Wurly. Munch really dotes on Wurly and wherever she goes, he follows, so I’m sure she provided some great comfort to him. The pair have always been inseparable and even had their first chick, Leek, in 2019 and are even incubating eggs once again!"

Munch is receiving daily eye drops but is quickly on the road to recovery, keepers say.

"He’s already swimming through the water faster, feeding with the group again and waddling around with ease. He’s a confident, happy little guy again!," Bissaker said.

Humboldt penguins are listed as vulnerable by the International Union for the Conservation of Nature (IUCN) Red List. The South American penguin is native to only Chile and Peru. There are fewer than 24,000 penguins left in the world and their population is decreasing.

They're named for the Humboldt Current, along which they commonly swim. In the wild, the penguins are threatened by disturbances in the food chain due to strong El Nino currents, as well as entanglements in fishing nets, egg predation by rats, and oil spills.

View Article Sources
  1. "Humboldt Penguin." IUCN Red List, 2020, doi:10.2305/