Swans along the River Thames are being inspected as part of the Queen's annual Swan Upping ceremony.
In the five-day ceremony which kicked off yesterday, swans up and down the river will be measured, tagged and given a health check to ensure they are well and uninjured.
Although it may look strange to see the birds getting handled by humans, the data collected from the ceremony will be used in the conservation and protection of the swans. Broods and baby swans known as Cygnets are also weighed and measured to obtain growth rates.
As part of the ceremony the Queen's Swan Marker and a group of Swan Uppers dress in traditional uniforms and take six rowing skiffs up the river, inspecting the swans and their brood as they go.
The Swan Uppers will be covering a stretch of water between Shepperton and Windsor, starting off at Shepperton Lock.
The tradition dates back to the 12th Century when the monarchy claimed ownership of all mute swans and the ceremony has been taking places for hundreds of years.