King Charles III Tallies Up Swans With 800-Year-Old Royal Tradition

King Charles may hold the title of the United Kingdom’s monarch, but he also possesses a more unique moniker: "Seigneur of the Swans."

The label essentially means that Charles, 75, is the owner of every wild, unmarked swan in England that roams the country’s rivers.

The sovereign put this title to good use on Friday, July 19, when he participated in a royal tradition called the “Swan Upping,” a tally that Charles takes every year of the swan populace on the River Thames.

The custom, which dates back to the 12th century, was facilitated by David Barber , the current Royal Swan Marker, earlier this weekend with his team. Barber and his group set out on a journey of the famous river’s 79-mile reach in order to count the white birds swimming around.

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The Royal Family shared a clip of the event via Instagram , showing the Swan Upping crew rowing in boats called “skiffs” to record the swans. The ships also held red flags that were branded with Charles’ royal emblem.

Through the centuries, British kings and queens would eat the swans as delicacies for lavish banquets. Nowadays, the annual census has changed from a ceremonial event to a significant part of wildlife conservation, according to the royal family’s official website.

Barber opened up to People in 2021 about the Swan Upping event, noting that the entire process takes only about 20 minutes to complete. “All the young cygnets [an adolescent swan] and adult birds have to be released together as the cygnets will get lost otherwise. So you have to be very, very careful. You face the cygnet to the parent bird, and then they will go off in the water together,” he said.

"Swans are large birds that weigh up to 15 kilograms [33 pounds]," Barber went on. "They have a wingspan of approximately 2.5 meters [8.2 feet], so they are a very large bird to deal with. They are heavy to get out of the water and, of course, they flap around quite a bit too."

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He added, “It's worth doing because if we didn't, the population of swans would just gradually disappear.” The tradition of the Swan Upping was even one plot point in season six of Netflix’s The Crown , which saw Queen Elizabeth II ( Imelda Staunton ) have a tiff with prime minister Tony Blair ( Bertie Carvel ) over how to improve the monarchy’s reputation.

Blair insists he can slash superfluous costs by eliminating certain employees of the royal household, such as the “warden of the swans,” though the Queen ultimately refuses.

The Swan Upping is Charles’ latest public outing as he continues to undergo treatment for an undisclosed type of cancer , having delivered a speech to Parliament at the Palace of Westminster on Wednesday, July 17.