The number of cygnets discovered on the River Thames in Windsor and Maidenhead has increased despite an outbreak of avian flu earlier this year.

This week saw the return of Swan Upping – an annual census of the mute swan population living on the River Thames.

The ceremony dates back to the 12th century when the Crown claimed ownership of all mute swans and today, the Crown retains the right of all unmarked mute swans in open water.

The conservation exercise sees a team of Royal Swan Uppers, who wear the scarlet uniform of the King, take to the water in traditional skiffs alongside Swan Uppers from the Vinters’ and Dyers’ Livery Companies.

During a five-day journey, crews are tasked with counting the number of cygnets on the river and ensuring the mute swan population is maintained.

The King’s Swan Marker, David Barber, said 32 cygnets were discovered on Monday on a stretch of the river between Sunbury Lock and Romney Lock in Windsor.

This was double the amount of cygnets found on the opening day of Swan Upping last year.

A further 32 cygnets were located on Tuesday between Eton Bridge and Marlow Lock – an increase of four from the same stretch of river in 2025.

Mr Barber said: “It’s not too bad. We thought it was going to be quite disastrous because we’ve had a lot of bird flu in the winter, which has really killed off a lot of the breeding pairs, so they’re down.

“However, some of the broods, or amount of offspring, are much larger than in previous years which is good.”

The mute swan population in Windsor and Maidenhead endured a devastating start to the year following an outbreak of suspected avian flu.

Bray-based swan rehabilitation charity, Swan Support, described the outbreak in January and February as like a ‘massacre’.

Cygnets also face the threat of predators including mink and birds of prey.

On Wednesday, the flotilla continued its journey along the River Thames, passing through locations including Hurley, Hambleden Lock and Henley Bridge.

The Swan Uppers also stopped off along the way to speak to groups of school children about their conservation work and wider threats facing the swan population. This includes the common threat of swans suffering injuries from fishing hooks.

The Swan Uppers are due to finish their conservation exercise today (Friday) with Abingdon Bridge, Oxfordshire, the final stop.