The Department of Conservation (DoC) is to put up signs warning kiteboarders not to disturb godwits near Whangarei.
Bird watchers complained last year when thousands of resting godwits were driven off by kite boarders at the Ruakaka river mouth.
DoC was in talks with kite boarders over the winter, aiming to set voluntary guidelines for the sport.
The agency is about to put up two large signs at the Ruakaka estuary, warning that sandbars at the river mouth are the only places left for the godwits to roost at certain high tides.
The signs warn that people who disturb the birds will be prosecuted. If the signs don't work, DoC says it will look at tougher restrictions.
However, Margaret Hicks says the Ruakaka estuary is simply too small to allow compromise. She says species like dotterel and oyster catchers, which try to breed there, are also at risk.
Ms Hicks claims monitoring last summer showed nests failed because the parent birds were frightened away by kite boarders.
