The octopus is a female, characterised by the nautilus shell on top of her head.
Produced from a thin secretion from the tips of two tentacles, it resembles the shape of a true nautilus shell.
Paper Nautilus are tropical animals, but occasionally schools of them are carried in ocean currents to New Zealand, where they become stranded in shallow waters around the northern coast.
Mr Ferguson said the octopus was not intact when it was found and one of its paddle-like flippers had broken off.
"I had to replicate it from the other one, the octopus uses them to scoop up her eggs before she retracts into the shell."
Mr Ferguson's studio has many examples of his previous work including deer, goats, dingoes, ducks and little flying squirrel.
He has been interested in taxidermy since he was at high school and he has worked as a tanner and taxidermist for more than 20 years.
Mr Ferguson expects there will be about 100 people at the championships over the weekend and there are likely to be 60 to 70 entries.
The judging panel is made up of local and international judges who are a mix of taxidermists and sculptors and there are men and women on the panel.
"Women tend to make better taxidermists because they have better fine motor skills," said Mr Ferguson.
His partner, Joan Le Noel, says she doesn't practise taxidermy although she does help out a bit.
"Sometimes I will notice that he doesn't have the eyes quite straight and I will tell him so," she says.
