BirdingNZ.net

I was sent this by people at Maungatautari. Any thoughts on what it is? It almost sounds frog or insect-like to me, but could it be a strange bird?

That sounds like frogs, we heard the same sound throughout the night when we were in makarora, and those were definitely frogs

You'd have the whistling tree frog down there. They are a bit chirpy. We only have the bell frogs around here, although people are known to move tree them around.

The call is similar to the whistling tree frog and they are in the North Island, could definitely have spread to Maungatautari by now. But it isn't an exact match, so I am not sure what it is. https://www.reptiles.org.nz/herpetofauna/non-native/litoria-ewingii

Yes, sounds like a whistling frog. Definitely neither of the large green frogs, whose calls are a lot deeper.

Have heard those in Westland, Greymouth very loud