Domestic flights across New Zealand - US citizen.?

I'm a US citizen and we are traveling to New Zealand. We will be flying into Wellington. One day while we are there, we would like to visit Auckland and I noticed airfare is cheap between the 2 cities. Instead of the 8 hour drive, I'd rather fly into Auckland in the morning and fly back to Wellington in the... show more I'm a US citizen and we are traveling to New Zealand. We will be flying into Wellington. One day while we are there, we would like to visit Auckland and I noticed airfare is cheap between the 2 cities. Instead of the 8 hour drive, I'd rather fly into Auckland in the morning and fly back to Wellington in the evening.

My question. Because I'm a US citizen, on a domestic route like that across New Zealand, do I have to go through customs and such even for a small flight like that? I don't want to spend 2-3 hours at each airport for a 45min-1hour flight. I would rather just take Auckland off of my travel plans while we are there if that is the case.

Thanks.
4 answers 4