A single Whooper Swan has been reported at Attenborough Nature Reserve for several days but only today (25/01) was I able to get sight of it among a group of Mute Swans quite close to the car park.
The Whooper Swan breeds in Iceland but spends the winter in the UK. I have had distant views of them at ANR but this is my first close view.

The most obvious difference between the Whooper Swan (left) and the Mute Swan (right) is the colour and shape of the bill and in the general facial area.