With duck shooting season about to begin Horizons Regional Council has called on hunters to be careful not to spread weeds between waterways.
Cleaning equipment will help avoid the spread of unwanted freshwater pests, including the invasive algae didymo and hornwort, says Horizons biosecurity programme coordinator for plants Craig Davey.
"Once in a waterway aquatic plant fragments can disperse and grow rapidly, destroying the environmental, recreational and aesthetic values of our waterways. We are asking hunters moving between waterways to check, clean, dry any equipment that has come into contact with river or lake water – particularly decoys and boots," Davey said.
"Some freshwater pests, like didymo and lake snow, are microscopic and can be spread by a single drop of water. It is very easy to spread pests without knowing you are."
Before leaving a waterway, hunters should check items and leave any weed or debris they find behind.