I caught a 16kg one as a kid on the east coast north of Gisborne. Didn't know at the time how bad the eel situation is It would've been about 20-25cm in diameter and 1.5m long. It was in a creek about a metre wide and quite shallow, I have found that is where you are most likely to find the biggest ones 8)
I got it with a pitchfork 8) I remember playing paper scissors rock with my mate to see who had to stab it :lol:
I now know not to take the really huge ones, as they are females. I know where 3 are on my parents property that are at least as big as the one I caught, but they are going to be left alone so they can have a chance to breed. They are all in creeks shallower than gumboots, that are very clear with a shingle bed. I have also seen some in Wairoa that would be similar sized, if not bigger