Wednesday 9 March 2016

Mute Swan x Black Swan

Mute Swan x Black Swan hybrid, West Midlands (UK), 13th January 2012 - copyright John Oates
(photo ID: 2734)


John tells us that this first-winter bird was the only surviving offspring of a male Mute Swan & a female Black Swan that nested at Marsh Lane Nature Reserve in 2011.  It disappeared shortly after this photo was taken.



Mute Swan Cygnus olo
Black Swan Cygnus atratus

2 comments:

  1. Looks like a mute swan to me. Can't find any characters from black swan, so why a hybrid? That a black and mute swan raised it doesn't mean that they are the parents.

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    Replies
    1. Hi Magnus, thanks for the comment. You are right to say that being raised by both species doesn't mean that it was necessarily the offspring of both, however I think this one is quite typical in appearance for Black Swan x Mute Swan hybrids. The speckling on the head and neck is atypical of pure Mute Swan of this age and typical of Black Swan x Mute Swan hybrids. Also pure Mute Swan of this age would be expected to have a clear-cut straight border between the reddish bill and the black at the base of the bill. If I saw this characteristic in isolation I might put it down as being aberrant, but together with the dark mottling on the head and neck and the coincidence of the accompanying adults I think it stacks up in favour of it being a hybrid. Always good to challenge these IDs though - we do make mistakes sometimes and always welcome comments like this.

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