Black Swans

Black Swans

Observation - Black Swans - UK and Ireland. Description: Although the picture of black swans was taken at Slimbridge last year my observation relates to a sighting on Friday 6th May at Dumbleton Hall, Dumbleton, just north of Cheltenham. Two Black Swans with five young cygnets. My question is that our Mute Swan

Although the picture of black swans was taken at Slimbridge last year my observation relates to a sighting on Friday 6th May at Dumbleton Hall, Dumbleton, just north of Cheltenham. Two Black Swans with five young cygnets. My question is that our Mute Swan is Cygnus olor but the Black Swan is Cygnus atratus, can they interbreed and do they ever do so? Also Mute cygnets are whitish when little but go grey and scruffy looking until they get their adult plumage at 1-2 years old, hence the story of the ugly duckling which didn't realise it was a beautiful swan. Now the Black swan cygnets we encountered were a lovely cream colour, and obviously still very young. When do they attain black feathers and do they go through any colour changes on the way to adulthood?