First of all, apologies for making a mess of the Gaelic title of the owl song in my previous message, It should be "Òran na Comhachaig".

Second, I've just found a recording of some verses of the song being sung at Tobar an Dualchais (http://www.tobarandualchais.co.uk/en/fullrecord/104342/1), but not to a tune with any similarity to the Mingulay Boat Song melody as far as I can detect.