Thanks for your comment Malcom. Santa Claus appears to have been used interchangeably with Father Christmas in New Zealand newspapers since around the 1870s. This fits with the description on this website about the history of Santa Claus and Father Christmas http://www.arthuriana.co.uk/xmas/pages/english.htm about the use of the names. It says from the 1870s onwards the English Father Christmas 'became increasingly like the American Santa Claus, both in terms of his actions - he started giving gifts - and his appearance, with the result that two are nowadays virtually inter-changeable'.