In a custom that dates back to the 12th century, representatives of the British royal family take to a flotilla of boats to count the swans along a stretch of the river Thames. The practice is known as Swan Upping.
Six small rowing boats, each with three crew along with support boats, cruise a stretch of river, covering 127 kilometers in five days. The Swan Uppers, as they are known, capture, tag, weigh and measure the birds in a bid to track their health.
A Swan Upper making an on-land inspection of new cygnets. /Catherine Drew/CGTN
This colorful tradition dates from a time when the British Crown claimed ownership of all unmarked mute swans to ensure a plentiful supply for medieval feasts. These days the ritual is still carried out, but with conservation in mind.
"The swan population has been pretty grim really," David Barber tells CGTN Europe. For the past three decades he's served as the Queen's, now King's, Swan Marker.
"It's only half the amount of cygnets so far this week we’ve actually caught compared with last year. We had bird flu that was disastrous at the end of last year and at the beginning of this year we lost over 400 birds on the river."
While avian flu has had a major impact on the UK's wild birds since the most recent outbreak in 2021, river pollution and vandalism have also taken a toll.
Swan Uppers inspecting the British Crown's swans. /Catherine Drew/CGTN
During an on-land inspection, Swan Upper Dan told CGTN Europe that flooding in late March and April also had an impact. "We had floods as the birds were starting to nest. Nests get washed away."
Indicating a swan family that have just been caught for weighing and tagging, he added: "These are fairly big cygnets but we have seen smaller ones. They were probably the result of a second brood, where they lost a clutch of eggs."
It's delicate work. The young cygnets, born in the spring, are just a few weeks old and the swans are very protective of their young. They're examined for disease and injuries, with many being treated on the river bank.
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"Now the young cygnets, they get tangled in fishing tackle a lot," King's Swan Marker Barber tells CGTN Europe. "We have serious problems with that, because they're not really streetwise like the adult birds. We have a lot of injuries like that and we take them to swan rescue organizations."
The work of the Swan Uppers draws crowds along the bank and in the river, with leisure boats laid on to observe the work and schoolchildren invited to the event launch.
While there is plenty of swan handling this week, the main message to the public is that these majestic birds should be left alone to enjoy their natural habitat in peace.
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