For five days each July, a small flotilla of traditional rowing skiffs makes its way up the Thames from Sunbury to Abingdon. The men aboard wear scarlet, cream and blue uniforms and feathered caps. When they spot a family of swans they cry “All up!”, surround the birds, and lift the cygnets out of the water.
Who owns the swans
The Crown. By a right dating from at least the twelfth century, the monarch owns all unmarked mute swans swimming in open water in Britain. The reason was culinary rather than sentimental: swan was a prestige food served at royal banquets, and ownership was worth asserting.
Two of the ancient London livery companies — the Vintners and the Dyers — were granted rights of ownership in the fifteenth century, and swan upping is essentially the annual reconciliation of the three sets of birds.
The Crown now exercises the right only on this stretch of the Thames, and nobody has eaten a royal swan for a very long time.
What actually happens
Historically the birds were marked with nicks on the beak to identify their owner — the origin of the pub name “The Swan with Two Necks”, a corruption of “two nicks”. That practice ended in 1978.
The exercise is now a genuine conservation survey. Cygnets are:
- lifted from the water and tied gently for handling;
- weighed and measured;
- checked for injury, particularly from fishing tackle and dog attacks;
- ringed with a British Trust for Ornithology identification ring;
- and released back to the parents.
The data has real value. It has tracked the collapse of Thames swan numbers from lead poisoning — lead fishing weights were banned in 1987 after swan upping evidence helped make the case — and their subsequent recovery.
The uniforms and the boats
The King’s Swan Marker wears scarlet with a white swan feather in his cap; the Vintners wear white and the Dyers blue. They row traditional Thames skiffs, and when passing Windsor Castle the crews stand to attention with oars raised and salute “Her Majesty the Queen, Seigneur of the Swans” — updated since 2022.
Watching it
The route and timetable are published in advance, and it is entirely free to watch from the bank. The boats move slowly and stop frequently, and the crews are happy to explain what they are doing. Local schools are often brought to see it, and the educational side is now treated as a major part of the point.
Swans and the law
The widely repeated claim that killing a swan is treason is not true. Mute swans are protected under the Wildlife and Countryside Act 1981 like any other wild bird, and harming one is a criminal offence with a fine or imprisonment — but it is ordinary wildlife law, not high treason.