"These freshwater pest species can have major impacts on waterways and affect the freshwater sports and activities that New Zealanders love."
MacDonald urges duck hunters who shoot from spots on different waterways to be extra vigilant.
"Before leaving a waterway, hunters should 'wash their weedy waders' by checking their gear and removing any visible weed or debris."
This involves checking, cleaning and drying all equipment that makes contact with the river or lake water, particularly decoys, decoy anchor lines, anchors, weights, boots and waders.
"This year, more than ever, we are all aware of appreciating and protecting what we've got, and keeping our waterways healthy for future generations is part of that."
Duck game hunting guidelines
* DOC district offices can issue game bird hunting permits for duck hunting on public conservation land and waters.
* Travel to your maimai to make preparations is allowed.
* Nationally travel and overnight stays, while following public health measures, is allowed.
* You can use boats
* Public conservation land will be open for game bird hunting but DOC huts and camping grounds have some guidelines.
* Maintain social distancing from people you don't know and keep a record of everyone you come in to contact with.
* Hunting groups are restricted to 10 people - the smaller the group the better.
* Hunt safely in areas you know and do not pose obvious risk.
* Avoid sharing equipment.
* Be safe in all your interactions.
* If you are sick or have any symptoms as minor as a runny nose - stay home.
- Hunting and Fishing NZ