New Zealand fishing operators fear rough waters ahead for the industry if a motion is carried at a conservation conference in Hawaii.

New Zealand Government delegates are at the International Union for Conservation of Nature.

It's not yet known if they'll vote on Motion 53, which would urge countries to turn 30 percent of national waters into no-fishing zones.

Charles Hufflett from Nelson-based fishing group Sollander told Rachel Smalley there has been little consultation with either fishing or iwi on the possible change.

"There's no indication where the 30% is. It could be near us where there is no fishing, we don't know where it is. The whole point is that there has been no discussion."