I’m an American who lived in New Zealand for two years (a lot of years ago). One way to get a New Zealander to quickly dismiss you as an idiot is to assume that ANYTHING that applies to Australia automatically applies to New Zealand. The history, geography, native culture and politics are very different.
There are no kangaroos in New Zealand. New Zealand was never an English penal colony. New Zealanders don’t speak with Australian accents. (Of course, in their opinion, they don’t speak with an accent at all. The rest of us do.)
Having said all that, there is a considerable number of Australians who live in New Zealand and there are a lot of words of Australian origin in New Zealand English – “sheila”, “back blocks”, “coo!” – but there is a much larger set of uniquely Australian words – “billabong”, “abo” – that set the speaker of as Australian, even in New Zealand.
New Zealand English is, in fact, surprisingly close to Standard British English (“the Queen’s English”) in pronunciation and vocabulary. There are, of course, frequently used native (Maori) terms, particularly for the names of plants and animals, geographical features, etc. But relatively few Maori words have become integrated into the common speech, much less so than, for example, in Hawaii. (Hawaiian and Maori are very closely related languages.) A few common Maori terms are understood by everyone (“maoritanga” – maori culture) but their usage depends on the speaker’s background. Maoris will use them among themselves and when speaking with “pakehas” but the English-ancestored seldom use them among themselves.
“non sunt multiplicanda entia praeter necessitatem”
– William of Ockham