The most common and most likely answer to this crossword clue is the 7 letter word TUATARA
T
U
A
T
A
R
A
More clues leading to the result TUATARA
Buddy explains!

The straight part
We know that "NZ resident" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nz resident = tuatara.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TUATARA mean?
TUATARA noun- Either of two reptiles, Sphenodon punctatus and Sphenodon guntheri, native to New Zealand, that resemble lizards.