The version of "A Duck" which is sung at Scout campfires in the UK varies from that in the DT, and follows.

A DUCK MAY BE SOMEBODY'S MOTHER

O be kind to your web footed friends,
For a duck may be somebody's mother,
It lives all alone in the swamp,
Where the weather is cold and damp.
Well you may think that this is the end,
Well it is, but to prove that I'm a liar
We'll sing the whole song again,
But only this time, alittle higher!


Repeat, (following a key change) for as many times as the voices in use can move upward. Once the song leader decides it is time to stop, he conducts, and cuts the song dead at "You may think that this is the end, well it is."
Tune Stars and Stripes Forever (Sousa)