In Conservation Week fishers could give some thought to improving habitat for the tiny fish, the department said.
They can also help by telling the department or regional council about overhanging culverts or other barriers that prevent the fish moving up and downstream.
Staff members will patrol fishing spots to make sure the rules are followed. If they are not fishers can be fined as much as $5000.
In February the department held a public forum in Whanganui on whitebait management.
Submissions on the department's 123-page Changes Proposed to Whitebait Management in New Zealand document closed in March.
It proposed ending the export of whitebait and creating refuges where whitebait cannot be caught. The Kai Iwi Stream was one of the refuges proposed.
Other measures would include changing the regulations and shortening the season - in Whanganui it would be shortened by six weeks, pulled back from November 30 to October 14.